Modeling Mediated Crossover Acute and Subacute Damage to the Pulmonary System During Systemic (Subcutaneous) Administration of Bleomycin in Mice to Test the Potential Therapeutic Effect of Polyphenols / Modelado del Daño Agudo y Subagudo Cruzado Mediado al Sistema Pulmonar Durante la Infección Sistémica (Subcutánea) de Administración de Bleomicina a Ratones para Probar el Posible Efecto Terapéutico de los Polifenoles

SUMMARY: The potential anti-inflammatory and antifibrotic activity of polyphenolic extracts of blueberry and grape was evaluated in a mouse model of lung damage induced by subcutaneous administration of bleomycin. The results of testing the polyphenolic extracts on two different systemic administration variants of bleomycin (intraperitoneal and subcutaneous) were compared. It was found that regardless of the method of bleomycin administration, indirect cross-acute and subacute damage to the pulmonary system was observed. Both patterns exhibited the same prevalence and severity. The administration of polyphenolic extracts of blueberry and grape to mice resulted in a significant decrease in theseverity of acute and subacute patterns of lung damage, suggesting their protective properties for the microcirculatory bed and a pronounced anti-inflammatory effect.

La potencial actividad antiinflamatoria y antifibrótica de los extractos polifenólicos de arándano y uva se evaluó en un modelo de daño pulmonar en ratón inducido por la administración subcutánea de bleomicina. Se compararon los resultados de las pruebas de los extractos polifenólicos en dos variantes diferentes de administración sistémica de bleomicina (intraperitoneal y subcutánea). Se encontró que, independientemente del método de administración de bleomicina, se observaba daño indirecto cruzado, agudo y subagudo al sistema pulmonar. Ambos patrones exhibieron la misma prevalencia y gravedad. La administración de extractos polifenólicos de arándano y uva a ratones dio como resultado una disminución significativa en la gravedad de los patrones agudos y subagudos de daño pulmonar, lo que sugiere sus propiedades protectoras del lecho micro- circulatorio y un efecto antiinflamatorio pronunciado.

Morphological Effects of Cigarette Smoking on Respiratory System and Related Functions Based on AQPs Expression

SUMMARY: A great deal of attention of air pollution on respiratory health is increasing, particularly in relation to haze days. It is that exposure to cigarette smoke augments the toxicity of common air contaminants, thereby increasing the complexity of respiratory diseases. Although there are various mechanisms involved to respiratory diseases caused or worsen by cigarette smoking, in which the role of AQPs in the lung with regard to fluid homeostasis still remains elusive. In this paper, we copied the rat models based on smoke generator, and investigated the morphological changes of mucosa and related functions depending on the balance of lining liquid of alveoli via AQPs expression. Compared with normal group, weak labelling of AQP1 and AQP5 protein abundance were clearly detected in the corresponding part of smoke exposure groups compared with normal group. Hence, it is suggested that the contribution of AQPs in the lung is diminished, thereby causing perturbed balancing between resorptive and secretory fluid homeostasis under cigarette smoking.

Cada vez se presta más atención a la contaminación del aire en la salud respiratoria, particularmente, en relación con los días de neblina. En consecuencia la exposición al humo del cigarrillo aumenta la toxicidad de los contaminantes comunes del aire, lo que además aumenta la complejidad de las enfermedades respiratorias. Aunque existen varios mecanismos involucrados en las enfermedades respiratorias causadas o empeoradas por el tabaquismo, en las que el papel de las AQP en el pulmón respecto a la homeostasis de líquidos sigue siendo difícil de alcanzar. En este artículo, copiamos los modelos de rata basados en el generador de humo e investigamos los cambios morfológicos de la mucosa y las funciones relacionadas según el equilibrio del líquido de revestimiento de los alvéolos a través de la expresión de AQP. En comparación con el grupo normal, se detectó claramente un etiquetado débil de la abundancia de proteínas AQP1 y AQP5 en la parte correspondiente de los grupos de exposición al humo en comparación con el grupo control. Por lo tanto, se sugiere que la contribución de las AQP en el pulmón está disminuida, provocando así un equilibrio perturbado entre la homeostasis del líquido secretor y de reabsorción bajo el hábito de fumar cigarrillos.

Pterostilbeno Reduz o Estresse Oxidativo no Pulmão e no Ventrículo Direito Induzido por Infarto do Miocárdio Experimental / Pterostilbene Reduces Experimental Myocardial Infarction-Induced Oxidative Stress in Lung and Right Ventricle

Resumo Fundamento O pterostilbeno (PS), um composto polifenólico natural e antioxidante, surge como uma intervenção promissora para minimizar danos do infarto agudo do miocárdio (IAM). Objetivo Este estudo teve como objetivo avaliar o desempenho do PS na promoção da homeostase redox nos pulmões e no ventrículo direito (VD) de animais infartados. Métodos Ratos Wistar machos (60 dias de idade) foram randomizados em três grupos: SHAM, IAM (infarto) e IAM+PS (IAM + pterostilbeno). Sete dias após o procedimento de IAM, os ratos foram tratados com PS (100 mg/kg/dia) por gavagem por oito dias. Os animais foram depois sacrificados e os pulmões e VD foram coletados para análise do balanço redox (diferenças foram consideradas significativas quando p<0,05). Resultados Nossos resultados mostram que o IAM desencadeia a interrupção redox no VD e nos pulmões, o que pode contribuir para danos induzido pelo IAM nesses órgãos. Consistentemente, o PS mitigou o estresse oxidativo e restaurou as defesas antioxidantes (Glutationa - GSH nos pulmões: SHAM = 0,79 ± 0,07; IAM = 0,67 ± 0,05; IAM + PS = 0,86 ± 0,14; p<0,05), indicando seu papel protetor neste cenário. Conclusão Nosso trabalho evidencia o potencial do uso de PS como abordagem terapêutica adjuvante após IAM para proteção dos tecidos pulmonares e cardíacos direitos.

Abstract Background Pterostilbene (PS), a natural and antioxidant polyphenolic compound emerges as a promising intervention in improving the myocardial infarction (MI) damages. Objetives This study aimed to evaluate PS actions in promoting redox homeostasis in lungs and right ventricle (RV) of infarcted animals. Methods Male Wistar rats (60 day-old) were randomized into three groups: SHAM, MI (infarcted), and MI+PS (MI+pterostilbene). Seven days after MI procedure, rats were treated with PS (100 mg/kg/day) via gavage for eight days. Animals were euthanized and the lungs and RV were harvested for analyses of redox balance (Differences were considered significant when p<0.05). Results Our results show that MI triggers a redox disruption scenario in RV and lungs, which can contribute to MI-induced damage on these organs. Consistently, PS mitigated oxidative stress and restored antioxidant defenses (GSH in lungs: SHAM= 0.79±0.07; MI=0.67±0.05; MI+PS=0.86±0.14; p<0.05), indicating its protective role in this scenario. Conclusions Our work evidences the PS potential use as an adjuvant therapeutic approach after MI focusing on protecting pulmonary and right-sided heart tissues.

Ameliorative effect of resveratrol against histological alterations in lung of mice induced by subchronic exposure of cigarette and waterpipe tobacco smoking / Efecto paliativo del resveratrol frente a las alteraciones histológicas en el pulmón de ratones inducidas por exposición subcrónica del tabaquismo de cigarrillos y pipas de agua

SUMMARY: This study aims to evaluate the ability of resveratrol (RSV) antioxidant to attenuate the oxidative stress condition induced by secondhand exposure of cigarettes and waterpipe smoking using animal model. Forty-eight mice were divided equally into six different groups, and RSV was delivered to certain groups intraperitoneally with a dose of 25 mg/kg/day. The process of smoking exposure was performed using a specialized smoking machine. The experiment duration lasts for six consecutive weeks. Five µm sections of lung were stained with hematoxylin and eosin for light microscopy, and 70 nm ultrathin sections of lung stained with uranyl acetate and lead citrate were prepared for transmission electron microscopy to observe the cellular ultrastructure. In lung, RSV reduced the deterioration and blebbing of bronchiole epithelium, reduced the inflammation, increased the surface area of alveolar sac, and reduced the thickening of alveolar walls. Also, blood vessels were less congested and less dilated with less diffusion of extravasated blood. Ultrastructural images illustrated that RSV protects the normal structure of alveolar septum, prevents DNA damage and alveolar degeneration, showed less degree of apical membrane blebbing and retained the uniform pattern of mitochondria. In conclusion, RSV has ameliorative effects against the oxidative stress condition induced by secondhand (side stream) exposure of cigarette and waterpipe tobacco smoking.

RESUMEN: Este estudio tiene como objetivo evaluar la capacidad del antioxidante resveratrol (RSV) para atenuar el estrés oxidativo inducido por la exposición de segunda mano a los cigarrillos y al tabaquismo en pipa de agua, utilizando un modelo animal. Se dividieron cuarenta y ocho ratones en seis grupos diferentes, y se administró RSV a ciertos grupos por vía intraperitoneal con una dosis de 25 mg / kg / día. El proceso de exposición al tabaquismo se realizó utilizando una máquina de fumar especializada. La duración del experimento fue de seis semanas consecutivas. Para realizar la microscopía óptica se tiñeron secciones de pulmón de cinco µm con hematoxilina y eosina, y se prepararon secciones ultrafinas de 70 nm de pulmón teñidas con acetato de uranilo y citrato de plomo para la microscopía electrónica de transmisión para observar la ultra estructura celular. En el pulmón, el RSV redujo el deterioro y la formación de ampollas del epitelio de los bronquiolos, redujo la inflamación, aumentó la superficie del saco alveolar y redujo el engrosamiento de las paredes alveolares. Además, los vasos sanguíneos se encontraron menos congestionados y menos dilatados y con menor difusión de sangre extravasada. Las imágenes ultraestructurales mostraron que el RSV protege la estructura normal del tabique alveolar, previene el daño del ADN y la degeneración alveolar, mostrando un menor grado de formación de ampollas en la membrana apical y además retuvo el patrón uniforme de las mitocondrias. En conclusión, el RSV tiene efectos de mejora contra el estrés oxidativo inducido por la exposición de segunda mano (corriente secundaria) al fumar cigarrillos y pipas de agua.

Impact of maternal exposure to wood smoke pollution on fetal lung morphology in a rat model / Impacto de la exposición materna a la contaminación por humo de leña en la morfología pulmonar fetal en un modelo de rata

SUMMARY: Residential heating with wood is an important source of ambient air pollution. Evidence links air pollution to serious health effects such as respiratory and cardiovascular mortality and morbidity. We hypothesized that prenatal exposure to wood smoke pollution causes morphological changes in the development of the rat lung, leading to altered lung structure and function during later life. We presumed that analysis of the fetal lung stereology provides novel insights into the underlying processes mediating particulate matter associated developmental changes and damage. The objective of the study was to investigate the effects of exposure during gestational period to wood smoke pollution on lung fetal morphology. To test this, pregnant rats were exposed during pregestational and gestational periods to wood smoke pollution. Complete lungs samples were obtained from 24 fetus from healthy female G3 rats subjected to cesarean at 19 days post-fecundation. The lungs were prepared for histological and stereological analysis. The volume fraction of terminal bronchioles VV [tb, lung] and volume fraction of parenchyma VV [par, lung], surface density of terminal bronchioles SV [tb, lung] as well as numerical density of bronchiolar exocrinocytes NA [ec,lung] were calculated by light microscopy. Statistical analysis detected significant differences between groups in volume density VV [tb, lung; %] (p=0.0012) and surface density SV [tb, lung; mm2/mm3] (p<0.0001) of the terminal bronchioles. However, it did not show differences between groups in the stereological parameter volume density VV [par, lung; %] (p=0.0838) and numerical density of bronchiolar exocrinocytes NA [ec,lung; nº/mm2] (p=0.0705). The analysis of the evidence obtained indicates that exposure to environmental pollution was affects lung maturation, and particularly the proportion and area of terminal bronchioles in the fetal lung. In conclusion, maternal exposure to wood smoke pollution during pregnancy was associated with a decrease in the lower conducting airways of lungs, which, according to urban pollution studies, could be related to early childhood lower respiratory illness. The public health implications of this study are that reducing or avoiding exposure to wood smoke is important before and during pregnancy.

RESUMEN: La calefacción residencial con leña es una fuente importante de contaminación ambiental. La evidencia vincula la contaminación del aire con graves efectos sobre la salud, como la mortalidad y la morbilidad respiratoria y cardiovascular. Hipotetizamos que la exposición prenatal a la contaminación por humo de leña causa cambios en el desarrollo del pulmón de rata, lo que conduce a una morfo-función pulmonar alteradas durante la vida posterior, creemos que el análisis de la estereología pulmonar fetal proporcionará nuevos conocimientos sobre los procesos subyacentes que median esos cambios. El objetivo del estudio fue investigar los efectos de la exposición prenatal a la contaminación ambiental por humo de leña sobre la morfología pulmonar fetal. Ratas preñadas fueron expuestas durante los períodos pregestacional y gestacional a la contaminación por humo de leña. En fetos de 19 días post-fecundación fue obtenido el pulmón para análisis histológico y estereológico. Fue determinado la fracción de volumen de bronquiolos terminales VV [tb, pulmón], fracción de volumen del parénquima VV [par, pulmón], densidad superficial de los bronquiolos terminales SV [tb, pulmón] así como la densidad numérica de exocrinocitos NA [ec, pulmón]. El análisis estadístico detectó diferencias significativas entre grupos en la densidad de volumen V [tb, pulmón; %] (p=0,0012) y densidad superficial SV [tb, pulmón; mm2/mm3] (p<0,0001) de los bronquiolos terminales. Sin embargo, no demostró diferencias entre grupos en la densidad de volumen VV [par, pulmón; %] (p=0,0838) y numérica de exocrinocitos bronquiolares NA [ec, pulmón; nº / mm ] (p=0,0705). El análisis de la evidencia obtenida indica que la exposición a la contaminación ambiental afectó la maduración pulmonar, y particularmente la proporción y área de bronquiolos terminales en el pulmón fetal. En conclusión, la exposición materna a la contaminación por humo de leña durante la gestación se asoció a una disminución de las vías respiratorias conductoras de aire en pulmón, lo que, según estudios de contaminación urbana, podría estar relacionado con enfermedades de las vías respiratorias inferiores en la primera infancia. Las implicaciones para la salud pública de este estudio son que reducir o evitar la exposición al humo de leña es importante previo y durante la gestación. Por otro lado, la contaminación por humo de leña tiene un gran impacto en la salud pública que, en teoría, es posible prevenir.

Efeitos da vareniclina no tecido pulmonar em modelo animal / Effects of varenicline on lung tissue in the animal model

RESUMO Objetivo O objetivo deste estudo foi investigar os efeitos agudos e crônicos da vareniclina no tecido pulmonar em um estudo experimental. Métodos Um total de 34 ratos foi alocado aleatoriamente em grupos de estudo (vareniclina) e controle. Assim, os ratos foram divididos em dois grupos: (i) grupo controle e (ii) grupo vareniclina. A seguir, os ratos de cada grupo foram, por sua vez, subdivididos igualmente em agudos (C1; V1) e crônicos (C2; V2), e todos os ratos dos grupos agudos e crônicos foram sacrificados sob anestesia: no 45.º dia, para o grupo agudo [C1 (n=5) e V1 (n=12)], e no 90.º dia, para o grupo crônico [C2 (n=5) e V2 (n=12)], respectivamente. Em seguida, foram realizadas análises bioquímicas e histopatológicas. Resultados Trinta e quatro ratos completaram o estudo. Destes ratos, 24 estavam no grupo vareniclina e 10 no grupo controle. Na exposição crônica à vareniclina, os níveis de oxidante composto por malondialdeído (MDA) e mieloperoxidase (MPO) aumentaram, e os níveis de superóxido dismutase (SOD), catalase (CAT), glutationa (GSH) e glutationa peroxidase (GPx), nomeados como antioxidantes, diminuiram significativamente quando comparados com o grupo controle. Os níveis de MDA e MPO também foram significativamente mais elevados e os níveis de SOD, CAT, GPx e GSH foram significativamente mais baixos no grupo vareniclina crônico, quando comparado ao grupo vareniclina agudo. Estes achados também foram confirmados por observações histopatológicas. Conclusões Este é o primeiro estudo que avaliou os efeitos pulmonares da vareniclina experimentalmente em um modelo animal. Observamos que o tratamento crônico da vareniclina causa inflamação e lesão pulmonar.

ABSTRACT Objective This study aimed to investigate acute and chronic effects of varenicline on lung tissue in an experimental study. Methods A total of 34 rats were randomly allocated into study (varenicline) and control groups. The rats were divided into two groups (i) control group, (ii) varenicline group. Then, the rats in the each group were sub-divided equally in turn as acute (C1; V1) and chronic (C2; V2) ; all rats of acute and chronic groups were sacrificed under the anesthesia on the 45th day for acute group [C1 (n=5) and V1 (n=12)] and the 90th day for chronic group [C2 (n=5) and V2 (n=12)], respectively. Thus, biochemical and histopathological analysis were carried out. Results Thirty four rats completed the study, 24 were in varenicline group and 10 were in control group. In chronic exposure to varenicline, oxidant levels comprising of malondialdehyde (MDA), and myeloperoxidase (MPO) increased and superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GPx) levels, named as antioxidants, decreased significantly when compared to the control group. MDA and MPO levels were also significantly higher and SOD, CAT, GPx, GSH levels were also significantly lower in chronic varenicline group when compared to acute varenicline group. These findings were also supported by histopathological observations. Conclusion This is the first study, which evaluated pulmonary effects of varenicline experimentally on an animal model. It was observed that chronic varenicline treatments cause inflammation and lung cell injury.

Investigation of the protective effect of enoxaparin and ticagrelor pretreatment against ischemia-reperfusion injury in rat lung tissue

SUMMARY OBJECTIVES This study was conducted to reveal the possible protective effects of ticagrelor and enoxaparin pretreatment against ischemia-reperfusion (IR)-induced injury on the lung tissue of a rat model. METHODS Wistar albino rats were randomly divided into 4 groups as follows: group-1 (control-sham), group-2 (control-saline+IR), group-3 (ticagrelor+IR), group-4 (enoxaparin+IR). Before the ischemic period, saline, ticagrelor, and enoxaparin were administered to the 2nd-4th groups, respectively. In these groups, IR injury was induced by clamping the aorta infrarenally for 2 h, followed by 4 h of reperfusion except group-1. After the rats were euthanized, the lungs were processed for histological examinations. Paraffin sections were stained with Haematoxylin&Eosin (H&E) for light microscopic observation. Apoptosis was evaluated by caspase-3 immunoreactivity. Data were statistically analyzed using the SPSS software. RESULTS In the lung sections stained with H&E, a normal histological structure was observed in group-1, whereas disorganized epithelial cells, hemorrhage, and inflammatory cell infiltration were seen in the alveolar wall in group-2. The histologic structure of the treatment groups was better than that of group-2. Caspase-3(+) apoptotic cells were noticeable in sections of group-2 and were lower in the treatment groups. In group-4, caspase-3 immunostaining was lower than in group-3. In group-2, apoptotic cells were significantly higher than in the other groups (p<0.001). CONCLUSION Based on the histological results, we suggested that both therapies ameliorated the detrimental effects of IR. Caspase-3 immunohistochemistry results also revealed that pre-treatment with enoxaparin gave better results in an IR-induced rat injury model. In further studies, other parameters such as ROS and inflammatory gene expressions should be evaluated for accurate results.

RESUMO OBJETIVOS Este estudo foi realizado para revelar os possíveis efeitos protetores do ticagrelor e do pré-tratamento da enoxaparina no tecido pulmonar contra o modelo de lesão induzida por isquemia-reperfusão (IR). MÉTODOS Ratos albinos Wistar foram randomizados e divididos em quatro grupos: grupo 1 (controle-sham), grupo 2 (controle-salina + IR), grupo 3 (ticagrelor + IR), grupo 4 (enoxaparina + IR). Antes do período isquêmico, salina, ticagrelor e enoxaparina foram administrados nos grupos 2-4, respectivamente. Nesses grupos, a lesão de IR foi induzida pelo clampeamento da aorta na região da infrarrenal por duas horas, seguida por quatro horas de reperfusão, exceto no grupo 1. Após a sacrificação, os pulmões foram processados para exames histológicos. Secções de parafina foram coradas com hematoxilina e eosina (H&E) para observação microscópica de luz. A apoptose foi avaliada pela imunorreatividade da caspase-3. Os dados foram analisados estatisticamente pelo programa SPSS. RESULTADOS Nas secções pulmonares coradas com H&E, estrutura histológica normal foi observada no grupo 1, enquanto células epiteliais desorganizadas, hemorragia e infiltração de células inflamatórias foram observadas na parede alveolar no grupo 2. A estrutura histológica dos grupos de tratamento foi melhor que o grupo 2. Células apoptóticas caspase-3 (+) foram notadas em secções do grupo 2, e essas células foram mais baixas nos grupos de tratamento. No grupo 4, a imunocoloração com caspase-3 foi menor que no grupo 3. No grupo 2, as células apoptóticas foram significativamente maiores que nos outros grupos (p<0,001). CONCLUSÃO Com base nos resultados histológicos, sugerimos que ambas as terapias atenuaram os efeitos prejudiciais da RI. Resultados de imuno-histoquímica com caspase-3 também revelaram que o pré-tratamento com enoxaparina proporcionou melhores resultados no modelo de lesão induzida por IR. Em estudos posteriores, outros parâmetros, como ROS e expressões gênicas inflamatórias, devem ser avaliados quanto a resultados precisos.

Betametasona fosfato para la prevención de Síndrome de Dificultad Respiratoria (SDR) del recién nacido de pretérmino / Betamethasone phosphate for the prevention of Respiratory Distress Syndrome (RDS) in the preterm newborn

RESUMEN Introducción: El estándar para inducción de madurez pulmonar en fetos con riesgo de nacer prematuramente es la administración de 12 mg de betametasona acetato/fosfato por dos veces espaciada cada 24 horas. El uso establecido en algunos hospitales públicos en Chile es con dos dosis de 12 mg betametasona fosfato aunque no existen estudios publicados sólo con betametasona fosfato sobre la incidencia de Síndrome de Distress Respiratorio (SDR). Objetivo: Evaluar efecto de betametasona en su forma fosfato como tratamiento antenatal para inducción de madurez fetal pulmonar en la incidencia SDR debido a membrana hialina en prematuros menores de 34 semanas de edad gestacional. Comparar el efecto de betametasona fosfato con el efecto publicado de betametasona acetato/fosfato. Material y método: Análisis de incidencia de SDR en prematuros nacidos en Hospital Padre Hurtado entre 24+0 y 34+0 semanas que recibieron betametasona fosfato para madurez pulmonar y aquellos que no la recibieron. Resultados: De 1.265 neonatos estudiados, 722 completaron dos dosis (57,5%); 436 sólo una dosis (34,5%) y 107 (8,5%) no recibieron corticoides antenatales. La incidencia de SDR debido a membrana hialina en el grupo con dos dosis fue 8,7%, una dosis 25,3% y 32,7% en los no tratados (p<0,001). Para SDR severo las incidencias fueron 6,7%, 12,6% y 16,8% respectivamente (p<0,001). Conclusiones: Inducción de madurez fetal pulmonar con betametasona fosfato en dos dosis de 12 mg IM separadas por 24 horas otorga una reducción significativa de incidencia de SDR semejante a la publicada con betametasona acetato/fosfato en iguales dosis.

ABSTRACT The standard for induction of lung maturity in fetuses at risk of being born prematurely is the administration of 12 mg of betamethasone acetate/phosphate two doses separated by 24 hours. The established use in some public hospitals in Chile is with two doses of 12 mg betamethasone phosphate although there are no studies published with betamethasone phosphate alone on the incidence of respiratory distress syndrome (RDS). Objective: To evaluate the effect of betamethasone in its phosphate form as antenatal treatment for the induction of fetal lung maturity in the incidence of RDS due to hyaline membrane in preterm infants less than 34 weeks of gestational age. To compare the effect of betamethasone phosphate with the published effect of betamethasone acetate/phosphate. Material and method: Analysis of the incidence of RDS in preterm infants born at Hospital Padre Hurtado between 24 + 0 and 34 + 0 weeks who received betamethasone phosphate for lung maturity and those who did not receive it. Results: Of 1,265 infants studied, 722 completed two doses (57.5%); 436 only one dose (34.5%) and 107 (8.5%) did not receive antenatal corticosteroids. The incidence of RDS due to hyaline membrane in the group with two doses was 8.7%, one dose 25.3% and 32.7% in the untreated ones (p <0.001). For severe RDS, incidences were 6.7%, 12.6% and 16.8% respectively (p <0.001). Conclusions: Induction of fetal lung maturity with betamethasone phosphate in two doses of 12 mg IM separated by 24 hours gives a significant reduction in the incidence of RDS similar to that published with betamethasone acetate/phosphate in equal doses.

Acrocomia crispa fruits lipid extract prevents LPS-induced acute lung injury in mice / Extracto lipídico de los frutos de Acrocomia crispa previene el daño pulmonar agudo inducido por LPS en ratones

The aim of this study was to evaluate the effects of single oral doses of D-005 (a lipid extract obtained from the fruit oil of Acrocomia crispa) on LPS-induced acute lung injury (ALI) in mice. D-005 batch composition was: lauric (35.8%), oleic (28.4%), myristic (14.2%), palmitic (8.9%), stearic (3.3%), capric (1.9%), caprylic (1.2%), and palmitoleic (0.05%) acids, for a total content of fatty acids of 93.7%. D-005 (200 mg/kg) significantly reduced lung edema (LE) (≈ 28% inhibition) and Lung Weight/Body Weight ratio (LW/BW) (75.8% inhibition). D-005 (25, 50, 100 and 200 mg/kg) produced a significant reduction of Histological score (59.9, 56.1, 53.5 and 73.3% inhibition, respectively). Dexamethasone, as the reference drug, was effective in this experimental model. In conclusion, pretreatment with single oral doses of D-005 significantly prevented the LPS-induced ALI in mice.

El objetivo de este estudio fue evaluar los efectos de dosis orales únicas de D-005 (extracto lipídico obtenido del aceite de frutos de Acrocomia crispa) sobre el daño pulmonar agudo (DPA) inducido por LPS en ratones. La composición del lote de D-005 fue: ácido láurico (35.8%), oleico (28.4%), mirístico (14.2%), palmítico (8.9%), esteárico (3.3%), cáprico (1.9%), caprílico (1.2%) y palmitoleico (0.05%), con un contenido total de ácidos grasos de 93.7%. D-005 (200 mg/kg) redujo significativamente el edema pulmonar (EP) (≈ 28% de inhibición) y la relación peso pulmón/peso corporal (PP/PC) (75.8% de inhibición). D-005 (25, 50, 100 y 200 mg/kg) produjo una reducción significativa de la puntuación histológica (59.9, 56.1, 53.5 y 73.3% de inhibición, respectivamente). La dexametasona, fármaco de referencia, fue efectiva en este modelo experimental. En conclusión, el pretratamiento con dosis orales únicas de D-005 previno significativamente el DPA inducido por LPS en ratones.

Effect of sevoflurane pretreatment in relieving liver ischemia/reperfusion-induced pulmonary and hepatic injury

Abstract Purpose To investigate the effect of sevoflurane preconditioning on ischemia/reperfusion (I/R)-induced pulmonary/hepatic injury Methods Fifty-one Wistar rats were randomly grouped into sham, I/R, and sevoflurane groups. After reperfusion, the structural change of the lung was measured by Smith score, the wet and dry weights (W/D) were determined, malondialdehyde (MDA) myeloperoxidase (MPO) content was determined colorimetrically and by fluorescence, respectively, and matrix metalloprotein-9 (MMP-9) mRNA was quantified by RT-PCR. Biopsy and morphological analyses were performed on liver tissue, activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were determined, and tumor necrosis factor-alpha (TNF-α) level was determined. Results The sham group showed no changes in tissue structure. Structural lesions in the sevoflurane and I/R groups were mild and severe, respectively. Smith score, W/D, MDA, MPO, and MMP mRNA showed the same trend, and were increased in the I/R group and recovered in the sevoflurane group, compared with the sham group (both P<0.05). AST and ALT were significantly increased compared to the sham group (AST: 655±52.06 vs . 29±9.30 U/L; ALT: 693±75.56 vs . 37±6.71 U/L; P<0.05). In the sevoflurane group, AST and ALT levels were significantly decreased (464±47.71 and 516±78.84 U/L; P<0.001). TNF-α presented similar results. Conclusion The protection of lung and liver by sevoflurane may be mediated by inhibited leukocyte recruitment and MMP-9 secretion.

Effects of intraperitoneal glutamine in the treatment of experimental sepsis / Efeitos da glutamina intraperitoneal no tratamento da sepse experimental

ABSTRACT Background: Sepsis is an important public health issue and is associated with high treatment costs and high mortality rates. Glutamine supplementation has proven to be beneficial to the functions of the immune system, acting beneficially in the evolution of patients in severe catabolic states. Aim: To evaluate the effect of glutamine supplementation via intraperitoneal in rats, induced sepsis, considering the following organs: intestines, liver, kidneys and lungs. Methods: Male Wistar rats subjected to sepsis by ligature and cecal puncture were divided into two groups: control C (n=6) and glutamine G (n=11), in which were administered dipeptiven 20% at a dose of 2 ml/kg/day (equivalent to 0.4g N(2)-L-alanyl-L-glutamine/kg) intraperitoneally 48 h prior to sepsis induction. After 48 h they were euthanized and intestine, liver, lung and kidney were removed for histological analysis. Results: Intestinal epithelial desquamation of the control group was more intense compared to the glutamine group (p=0.008). In the kidneys, degenerative tubular epithelial changes were less severe in the animals that received glutamine (p=0.029). Regarding to the liver, glutamine group showed lower levels of cell swelling than the control group (p=0.034). In the lung there were no results with statistical significance. Conclusion: Prior intraperitoneal supplementation with glutamine in experimental animals is able to reduce the damage to the intestinal mucosa, to the kidneys and liver's histoarchitecture.

RESUMO Racional: A sepse é importante problema de saúde pública, sendo relacionada com altos custos de tratamento e elevadas taxas de mortalidade. A suplementação de glutamina tem provado ser benéfica às funções do sistema imune, atuando em estados catabólicos graves. Objetivo: Avaliar o efeito da suplementação de glutamina via intraperitoneal em ratos induzidos à sepse. Método: Foram utilizados ratos Wistar submetidos à sepse por ligadura e punção do ceco, separados em grupo controle C (n=6) e glutamina G (n=11), aos quais foram administrados dipeptiven a 20% com dose de 2 ml/kg/dia (equivalente a 0,4 g N(2)-L-alanil-L-glutamina/kg), via intraperitoneal, 48 h antes da indução da sepse. Após 48 h todos os animais foram submetidos à eutanásia e intestino, fígado, pulmão e rim foram retirados para análise histológica. Resultados: No intestino a descamação epitelial do grupo controle foi mais intensa em comparação ao da glutamina (p=0,008). Nos rins, houve menor degeneração do epitélio tubular nos animais que receberam glutamina (p=0,029). No fígado, o grupo glutamina apresentou índices menores de tumefação celular do que o grupo controle (p=0,034). No pulmão não houve resultados com significância estatística. Conclusão: A suplementação prévia de animais experimentais com glutamina via intraperitoneal é capaz de reduzir os danos causados à mucosa intestinal, histoarquitetura dos rins e do fígado.

Melatonin effects on pulmonary tissue in the experimental model of Hepatopulmonary Syndrome / Efeitos da melatonina sobre o tecido pulmonar no modelo experimental de Síndrome Hepatopulmonar

ABSTRACT Objective: To evaluate the pulmonary alterations of animals with Hepatopulmonary Syndrome (HPS) submitted to Biliary Duct Ligature (BDL), as well as the antioxidant effect of Melatonin (MEL). Methods: Sixteen male Wistar rats, divided into four Sham groups: BDL group, Sham + MEL group and BDL + MEL. The pulmonary and hepatic histology, lipoperoxidation and antioxidant activity of lung tissue, alveolar-arterial O2 difference and lung / body weight ratio (%) were evaluated. Results: When comparing the groups, could be observed an increase of vasodilation and pulmonary fibrosis in the BDL group and the reduction of this in relation to the BDL + MEL group. It was also observed significant changes in the activity of catalase, ApCO2, ApO2 in the LBD group when compared to the other groups. Conclusion: The use of MEL has been shown to be effective in reducing vasodilation, fibrosis levels and oxidative stress as well as gas exchange in an experimental HPS model.

RESUMO Objetivo: Avaliar as alterações pulmonares de animais com Síndrome Hepatopulmonar (SHP), submetidos à ligadura de ducto biliar (LDB), bem como o efeito antioxidante da Melatonina (MEL). Métodos: Dezesseis ratos machos da espécie Wistar, divididos em quatro grupos: Sham, Grupo LDB, Grupo Sham + MEL e LDB + MEL. Foram avaliadas a histologia pulmonar e hepática, a lipoperoxidação e atividade antioxidante do tecido pulmonar, diferença álveolo-arterial de O2 e relação peso pulmonar/peso corporal (%). Resultados: Quando comparados os grupos, observamos um aumento da vasodilatação e fibrose pulmonar no grupo LDB e a redução deste em relação ao grupo LDB+MEL. Observamos ainda alterações significativas na atividade da catalase, PaCO2, PaO2 no grupo LBD quando comparado aos demais grupos. Conclusões: A utilização da MEL demonstrou-se eficaz na redução da vasodilatação, níveis de fibrose e estresse oxidativo assim como na troca gasosa em modelo experimental de SHP.

Effect of vaporized perfluorocarbon on oxidative stress during the cold ischemia phase of lung graft preservation / Efeito do perfluorocarbono vaporizado sobre o estresse oxidativo no período de isquemia fria durante a preservação pulmonar

ABSTRACT Liquid perfluorocarbon (PFC) instillation has been studied experimentally as an adjuvant therapy in the preservation of lung grafts during cold ischemia. The objective of this study was to evaluate whether vaporized PFC is also protective of lung grafts at different cold ischemia times. We performed histological analysis of and measured oxidative stress in the lungs of animals that received only preservation solution with low-potassium dextran (LPD) or vaporized PFC together with LPD. We conclude that vaporized PFC reduces the production of free radicals and the number of pulmonary structural changes resulting from cold ischemia.

RESUMO O perfluorocarbono (PFC) líquido tem sido estudado experimentalmente como uma substância adjuvante na preservação de enxertos pulmonares durante o período de isquemia fria. O objetivo deste estudo foi avaliar se o PFC vaporizado (e não instilado) também atuaria como protetor de enxertos pulmonares em diferentes tempos de isquemia fria. Realizamos análise histológica e dosamos o estresse oxidativo em pulmões de animais que receberam somente uma solução de preservação com low-potassium dextran (LPD, dextrana com baixa concentração de potássio) ou PFC vaporizado associado a LPD. Concluímos que o PFC vaporizado reduziu a produção de radicais livres e provocou menor número de alterações estruturais pulmonares decorrentes do período de isquemia fria que o uso de LPD isoladamente.

Internações hospitalares e impacto financeiro por tuberculose pulmonar na Bahia, Brasil / Internamientos hospitalarios e impacto financiero por Tuberculosis Pulmonar en Bahía, Brasil / Hospital admissions and financial impact due to Pulmonary Tuberculosis in Bahia, Brazil

Resumo Este estudo teve como objetivo descrever os casos de internações hospitalares e impacto financeiro da tuberculose pulmonar no estado da Bahia, Brasil, entre o período de 2012 e 2016. É um estudo epidemiológico, descritivo transversal, utilizando dados do Departamento de Ciência da Computação do Sistema Único de Saúde. As variáveis coletadas foram: sexo, faixa etária, valores dos serviços hospitalares e raça, relatadas no período de 2012 e 2016. Os casos de internações hospitalares foram selecionados de acordo com o capítulo I da 10ª Classificação Estatística Internacional de Doenças e Problemas de Saúde, incluindo as categorias entre A15.0 e A15.3. Entre os resultados, constatou-se que no período estudado, foram registrados 5.593 casos de internações hospitalares por tuberculose pulmonar no estado da Bahia, o que corresponde a 0,14% do total de internações hospitalares. A maior prevalência ocorreu na macro região oriental (n = 4.623), entre os homens (n = 4.079), entre 40 e 49 anos (n = 1.361) e cor / raça ignorada (n = 5.176). A tuberculose pulmonar gerou um impacto financeiro na Bahia de mais de 7 milhões de reais no período estudado e a macrorregião oriental gerou maiores gastos para o estado, correspondendo a 91,70% do total de custos hospitalares. Conclui-se que na macro região oriental, o modo de distribuição dos casos de internações hospitalares por tuberculose pulmonar faz da macrorregião uma prioridade para as ações de controle e prevenção da patologia.

Resumen Este estudio tuvo como objetivo describir los casos de internamientos hospitalarios y el impacto financiero por tuberculosis pulmonar en el estado de Bahía, Brasil entre el periodo 2012 y 2016. Es un estudio epidemiológico, descriptivo y transversal, utilizando los datos obtenidos en el Departamento de Informática del Sistema Único de Salud. Las variables recolectadas fueron: sexo, grupo de edad, valores de los servicios hospitalarios y raza, notificados en el período de 2012 y 2016. Los casos de internamientos hospitalarios han sido seleccionados de acuerdo con el capítulo I de la 10ª Clasificación Estadística Internacional de Enfermedades y Problemas de Salud, comprendiendo las categorías entre A15.0 y A15.3. Entre los resultados se obtuvo que en el período estudiado, se han registrado 5.593 casos de internamientos hospitalarios por tuberculosis pulmonar en el estado de Bahía, que corresponde a 0,14% del total de las hospitalizaciones. La mayor prevalencia ocurrió en la macro región Este (n=4.623), entre personas de sexo masculino (n=4.079), de grupo etario entre 40 y 49 años (n=1.361) y color/raza ignorada (n=5.176). La tuberculosis pulmonar ha generado en Bahía un impacto financiero superior a 7 millones de reales en el período estudiado y la macro región Este ha generado mayor gasto al estado, correspondiendo a 91,70% del total de los costos hospitalarios. Se concluye que en la macro región Este, el modo de distribución de los casos de internamientos hospitalarios por tuberculosis pulmonar convierte la macro región como prioritaria para las acciones de control y prevención de la patología.

Abstract The purpose of this study was to describe the cases of hospital admissions and the financial impact of pulmonary tuberculosis in the state of Bahia, Brazil between 2012 and 2016. It is an epidemiological, descriptive and cross-sectional study, using the data obtained in the Department of Information Technology of the Unified Health System. The variables collected were: sex, age group, values of hospital services and race, reported in the period of 2012 and 2016. The cases of hospital admissions have been selected in accordance with chapter I of the 10th International Statistical Classification of Diseases and Health Problems, including the categories between A15.0 and A15.3. Among the results, it was found that in the period studied, 5,593 cases of hospital admissions for pulmonary tuberculosis in the state of Bahia were registered, which corresponds to 0.14% of the total number of hospitalizations. The highest prevalence occurred in the Eastern macro region (n = 4,623), between male people (n = 4,079), between 40 and 49 years old (n = 1,361) and color / race ignored (n = 5,176). Pulmonary tuberculosis has generated a financial impact in Bahia of more than 7 million reales in the period studied and the Eastern macro region has generated greater spending to the state, corresponding to 91.70% of total hospital costs. It is concluded that in the Eastern macro region, the mode of distribution of cases of hospital admissions for pulmonary tuberculosis makes the macro region a priority for the actions of control and prevention of the pathology.

Effectual components of Polygonum ciliinerve protects against Staphylococcus aureus infection with immunomodulatory functions in C57BL/6 mice

Abstract Purpose: To investigate the efficacy and mechanisms of root tuber of Polygonum ciliinerve (Nakai) ohwi (rPC) which has been used to treat bacterial infection in traditional Chinese medicine. Methods: With the mouse model of Staphylococcus aureus (S. aureus) pneumonia, the phenotype of rPC treated mice, including body weight, mortality, lung slices and bacterial burden were evaluated. Furthermore, inflammatory factors in bronchoalveolar lavage (BAL) were determined by ELISA and the distribution of T cells in lung was assessed by immunofluorescence assay. Results: rPC treatment could dose-dependently reduce weight loss and mortality in S. aureus-infected mice. Upon 10 mg/ml rPC treatment, S. aureus-infected mice showed about 8 grams increase in body weight (P<0.001) and 50% enhancement in mortality. The integrity of lung tissue and bacterial burden were also improved by rPC treatment. Moreover, rPC was found to modulate the immune response in infection. Conclusion: rPC has therapeutic potential for S. aureus infections and pneumonia with immunomodulatory functions.

Protein from Hevea brasiliensis "Hev b 13" latex attenuates systemic inflammatory response and lung lesions in rats with sepsis / Proteína do latex de Hevea brasiliensis "Hev b 13" atenua resposta inflamatória sistêmica e lesão pulmonar de ratos com sepse

Abstract Sepsis induces a severe systemic inflammatory response that may result in multiple organ dysfunction and death. Studies using a protein derived from natural Hevea brasiliensis (rubber tree) latex, denominated Hev b 13, have demonstrated important anti-inflammatory effects, but no data have been published regarding its effects on sepsis. The aim of this study was to investigate the effects of Hev b 13 on the inflammatory response and lung lesions of septal rats. Male Wistar rats were submitted to cecal ligation and puncture (CLP), randomized into groups and treated with subcutaneously administered doses of 0.5/2.0/3.0 mg/Kg of Hev b 13. Next, animals were subdivided into three different points in time (1, 6 and 24 hours after treatments) for collection of blood samples and euthanasia accompanied by organ removal. Total and differential leukocyte counts, cytokine dosage and histological assessment were analyzed. Treatment with Hev b 13 resulted in a significant decline in total and differential leukocytes as well as suppression of TNF-α and IL-6 production, associated with the increase in IL-10 and IL-4 in plasma and lung tissue. Moreover, it reduced morphological and pathological changes found in the lungs, including neutrophil infiltration, edema and alveolar thickening. The present study concluded that Hev b 13 exerts anti-inflammatory effects and attenuates lung lesions in septal rats, showing potential for clinical application.

Resumo Sepse induz uma resposta inflamatória sistêmica grave podendo resultar em disfunção de múltiplos órgãos e morte. Pesquisas utilizando uma proteína derivada do látex natural de Hevea brasiliensis (seringueira), denominada Hev b 13 tem demonstrado importantes efeitos anti-inflamatórios, mas nenhum dado foi publicado dos seus efeitos na sepse. O objetivo deste estudo foi investigar os efeitos da Hev b 13 na resposta inflamatória e na lesão pulmonar de ratos com sepse. Ratos machos da linhagem Wistar foram submetidos a ligação e perfuração do ceco (LPC), randomizados em grupos e tratados com as doses 0,5/2,0/3,0 mg/Kg de Hev b 13 subcutâneo. Após subdividiu-se os animais em três pontos diferentes de tempo (1, 6 e 24 horas após os tratamentos) para coleta de amostras sanguíneas e eutanásia com remoção dos órgãos. Contagem total e diferencial de leucócitos, dosagem de citocinas e avaliação histológica foram analisadas. O tratamento com a Hev b 13 resultou em diminuição significativa de leucócitos totais e diferenciais bem como suprimiu a produção de TNF-α e IL-6, associado ao aumento de IL-10 e IL-4 no plasma e tecido pulmonar. Além disso, reduziu as alterações morfológicas e patológicas encontradas nos pulmões, incluindo infiltrado de neutrófilos, edema e espessamento alveolar. Este estudo concluiu que a Hev b 13 tem efeitos anti-inflamatórios e atenua lesões pulmonares em ratos com sepse, apresentando potencialidades para aplicabilidade clínica.

Effect of melatonin on antioxidant capacity, inflammation and apoptotic cell death in lung tissue of diabetic rats

Abstract Purpose: To investigate the effects of melatonin on antioxidant capacity, inflammation and apoptotic cell death (through expression of cleaved-caspase 3) in lung tissue samples of diabetic rats. Methods: Thirty male Sprague-Dawley rats were randomly divided into three groups. Group 1 (control group) was made up of healthy rats. Group 2 (diabetes group) received streptozotocin at a dose of 50 mg/kg/day for 5 days.Group 3 (diabetes plus melatonin group) received streptozotocin at a dose of 50 mg/kg/day for 5 days and then they received melatonin at a dose of 20 mg/kg/day between 28thand 35thdays of the study. Results: Tissue MDA and MPO levels were found to be significantly higher in diabetes group compared to control group (p<0.05) whilst administration of melatonin was found to significantly lower this increase down to normal levels (p<0.05). Bronchus associated lymphoid tissue (BALT) was more severe in diabetics whereas administration of melatonin alleviated this hyperplasia. Cleaved caspase 3 activity was severe in hyperplastic BALT in diabetic rats however in lowered down to moderate level when melatonin was administered. Conclusion: The melatonin caused an increase in antioxidant capacity and decreased the expression of cleaved-caspase 3.

Effects of propofol pretreatment on lung morphology and heme oxygenase-1 expression in oleic acid-induced acute lung injury in rats

Abstract Purpose: To investigate the effects of propofol pretreatment on lung morphology and heme oxygenase-1 expression in oleic acid -induced acute lung injury in rats. Methods: A total of 32 male Sprague-Dawley rats (250-300g) were randomly divided into the following four groups (n=8/group): group C, group OA, group OA+PR, and group OA+IX to compare related parameter changes. Results: PaO2, PCO2, and PaO2/FiO2 were significantly different among the four treatment groups (P<0.05 or P<0.01). Lung wet/dry weight ratio and HO-1 protein expression also significantly differed among the groups (P<0.01). Immunohistochemistry showed that the expression of HO-1 in group OA+PR was stronger than those in groups OA, OA+IX, and C. Light microscopy revealed that pathological changes in lung tissues in group OA+PR were milder than those in group OA and group OA+IX. Electron microscopy showed that alveolar type II epithelial cell ultrastructure in group OA was relatively irregular with cell degeneration and disintegration and cytoplasmic lamellar bodies were vacuolized. Changes in group OA+PR were milder than those in group OA; however, they were more severe in group OA+IX than in group OA. Conclusion: Propofol significantly increases the expression of HO-1 in the lung tissueand prevents changes in lung morphology due to ALI in rats.

Local and systemic effects of fibrin and cyanoacrylate adhesives on lung lesions in rabbits

OBJECTIVES: Tissue adhesives can be used to prevent pulmonary air leaks, which frequently occur after lung interventions. The objective of this study is to evaluate local and systemic effects of fibrin and cyanoacrylate tissue adhesives on lung lesions in rabbits. METHODS: Eighteen rabbits were submitted to videothoracoscopy + lung incision alone (control) or videothoracoscopy + lung incision + local application of fibrin or cyanoacrylate adhesive. Blood samples were collected and assessed for leukocyte, neutrophil and lymphocyte counts and interleukin-8 levels preoperatively and at 48 hours and 28 days post-operatively. After 28 days, the animals were euthanized for gross examination of the lung surface, and lung fragments were excised for histopathological analysis. RESULTS: Fibrin and cyanoacrylate produced similar adhesion scores of the lung to the parietal pleura. Microscopic analysis revealed uniform low-cellular tissue infiltration in the fibrin group and an intense tissue reaction characterized by dense inflammatory infiltration of granulocytes, giant cells and necrosis in the cyanoacrylate group. No changes were detected in the leukocyte, neutrophil or lymphocyte count at any time-point, while the interleukin-8 levels were increased in the fibrin and cyanoacrylate groups after 48 hours compared with the pre-operative control levels (p<0.01). CONCLUSION: Both adhesive agents promoted normal tissue healing, with a more pronounced local inflammatory reaction observed for cyanoacrylate. Among the serum markers of inflammation, only the interleukin-8 levels changed post-operatively, increasing after 48 hours and decreasing after 28 days to levels similar to those of the control group in both the fibrin and cyanoacrylate groups.

Functional respiratory imaging after neostigmine- or sugammadex-enhanced recovery from neuromuscular blockade in the anesthetised rat: a randomised controlled pilot study / Imagem funcional da respiração após aceleração da recuperação do bloqueio neuromuscular com neostigmina ou sugamadex em ratos anestesiados: estudo piloto controlado e randomizado

Abstract Objectives Reductions in diaphragm activity are associated with the postoperative development of atelectasis. Neostigmine reversal is also associated with increased atelectasis. We assessed the effects of neostigmine, sugammadex, and spontaneous reversal on regional lung ventilation and airway flow. Methods Six Sprague-Dawley rats were paralysed with rocuronium and mechanically ventilated until recovery of the train-of-four ratio to 0.5. We administered neostigmine (0.06 mg.kg-1), sugammadex (15 mg.kg-1), or saline (n = 2 per group). Computed tomography scans were obtained during the breathing cycle. Three-dimensional models of lung lobes were generated using functional respiratory imaging technology, and lobar volumes were calculated during the breathing cycle. The diaphragmatic surface was segmented for the end-expiratory and end-inspiratory scans. The total change in volume was reported by the lung volume change from the end-expiratory scan to the end-inspiratory scan. Chest wall movement was defined as the lung volume change minus the volume change that resulted from diaphragm excursion. Results The two rats that received neostigmine exhibited a smaller relative contribution of diaphragm movement to the total change in lung volume compared with the two rats that received sugammadex or saline (chest wall contribution (%): 26.69 and 25.55 for neostigmine; -2.77 and 15.98 for sugammadex; 18.82 and 10.30 for saline). Conclusion This pilot study in rats demonstrated an increased relative contribution of chest wall expansion after neostigmine compared with sugammadex or saline. This smaller relative contribution of diaphragm movement may be explained by a neostigmine-induced decrease in phrenic nerve activity or by remaining occupied acetylcholine receptors after neostigmine.

Resumo Objetivos As reduções da atividade do diafragma estão associadas ao desenvolvimento de atelectasia no período pós-operatório. A reversão com neostigmina também está associada ao aumento de atelectasia. Avaliamos os efeitos de neostigmina, sugamadex e da reversão espontânea sobre a ventilação pulmonar regional e o fluxo aéreo. Métodos Seis ratos Sprague-Dawley foram paralisados com rocurônio e mecanicamente ventilados até a recuperação da sequência de quatro estímulos atingir relação 0,5. Administramos neostigmina (0,06 mg.kg-1), sugamadex (15 mg.kg-1) ou solução salina (n = 2 por grupo). As tomografias foram feitas durante o ciclo respiratório. Modelos tridimensionais dos lobos pulmonares foram gerados com a tecnologia de imagem funcional respiratória e os volumes lobares foram calculados durante o ciclo respiratório. A superfície diafragmática foi segmentada para as varreduras expiratória final e inspiratória final. A alteração total no volume foi relatada pela alteração do volume pulmonar da varredura expiratória final para a varredura inspiratória final. O movimento da parede torácica foi definido como a variação do volume pulmonar menos a alteração no volume resultante da excursão do diafragma. Resultados Os dois ratos que receberam neostigmina apresentaram uma contribuição relativa menor do movimento do diafragma para a alteração total do volume pulmonar em comparação com os dois ratos que receberam sugamadex ou solução salina (contribuição da parede torácica (%): 26,69 e 25,55 para neostigmina; -2,77 e 15,98 para sugamadex; 18,82 e 10,30 para solução salina). Conclusão Este estudo piloto com ratos demonstrou uma contribuição relativa aumentada de expansão da parede torácica após neostigmina em comparação com sugamadex ou solução salina. Essa contribuição relativa menor de movimento do diafragma pode ser explicada por uma redução induzida por neostigmina na atividade do nervo frênico ou por receptores de acetilcolina permanecerem ocupados após a administração de neostigmina.