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OBJECTIVES: Skeletal muscle dysfunction is one of the most common comorbidities in chronic obstructive pulmonary disease (COPD). The occurrence of respiratory failure in COPD is common and leads to the patient's death. The diaphragm is the most important muscle in the respiratory system and plays a key role in the onset of respiratory failure. This study explores the feasibility of ultrasound shear wave elastography (SWE) to measure diaphragmatic stiffness and evaluates its changes in COPD patients. METHODS: In total, 77 participants (43 patients with stable COPD and 34 healthy controls) were enrolled. All subjects underwent complete diaphragmatic ultrasound SWE measurements and pulmonary function tests. The diaphragmatic stiffness was indicated via diaphragmatic shear wave velocity (SWV) at functional residual capacity (FRC). A trained operator performed the ultrasound SWE examinations of the first 15 healthy controls thrice to assess the reliability of diaphragmatic SWE. RESULTS: A good to excellent reliability was found in diaphragmatic SWV at FRC (ICC = 0.93, 95%CI 0.82-0.98). As compared to the control group, the diaphragmatic SWV at FRC was considerably high in the COPD group (median 2.5 m/s versus 2.1 m/s, P = .008). Diaphragmatic SWV at FRC was linked to forced expiratory volume in one second (r = -0.30, P = .009), forced vital capacity (r = -0.33, P = .003), modified Medical Research Council score (r = 0.30, P = .001), and COPD assessment test score (r = 0.48, P < .001). CONCLUSIONS: Ultrasound SWE may be employed as an effective tool for quantitative evaluation of diaphragm stiffness and can help in personalized management of COPD, such as treatment guidance and follow-up monitoring.
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Técnicas de Imagem por Elasticidade , Doença Pulmonar Obstrutiva Crônica , Diafragma/diagnóstico por imagem , Humanos , Projetos Piloto , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Reprodutibilidade dos TestesRESUMO
PURPOSE: The sleep disorder in pregnant women remains unfamiliar to perinatal care providers, resulting in lack of appropriate care. This study was designed to investigate the prevalence of sleep disorder-related symptoms in pregnant women and to identify the associated risk factors. METHODS: Married pregnant women were enrolled from their first trimester and followed up until delivery. Nonpregnant married healthy women were selected as controls. A survey questionnaire was administered to each of them. RESULTS: We successfully performed a survey to 1,993 pregnant women and 598 nonpregnant women. The overall prevalence of sleep disorder-related symptoms in pregnant women was significantly higher than the controls (56.1 vs. 29.9 %, P < 0.05). There was higher prevalence of snoring (30.2 %), observed sleep apnea (1.1 %), mouth breathing (23.7 %), nocturnal arousal (46.5 %), insomnia (35.1 %), and daytime sleepiness (52.6 %) in pregnant women. There were no significant differences of the prevalence of bruxism (7.0 vs. 6.7 %), sleep talking (8.1 vs. 7.2 %), and sleep walking (0.4 vs. 0.2 %) between the two groups (P > 0.05). Nocturnal sleep time (8.0 ± 1.3 h) was less in the third trimester compared with the nonpregnant women (8.2 ± 1.1 h) (P < 0.05). Smoking (OR = 3.39), drinking (OR = 2.40), allergic rhinitis/asthma (OR = 1.71), an obvious difference in neck circumference (OR = 1.11), and waistline (OR = 1.07) changes between the first and third trimesters were the risk factors for sleep disorder-related problems. CONCLUSIONS: There is a high prevalence of sleep disorder-related symptoms in pregnant women. Our data may provide a baseline for prevention and treatment of sleep disturbances in pregnant women.
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Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/epidemiologia , Adolescente , Índice de Massa Corporal , China , Estudos Transversais , Feminino , Seguimentos , Idade Gestacional , Inquéritos Epidemiológicos , Humanos , Gravidez , Fatores de Risco , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Inquéritos e Questionários , Circunferência da CinturaRESUMO
Background: Tobacco cessation is proven to be the most effective and cost-effective strategy for smokers to reduce their risk of smoking-related disease and premature death. Providing effective, efficient, safe, and patient-centred tobacco cessation treatment to reach those who need them is a significant challenge. To date, only a few nationwide studies in China have assessed the overall clinical care practice and treatment outcome of tobacco cessation. Methods: This a prospective, nationwide, multicenter, cohort study covering all Eastern China, Northwest China, Central China, North China, Southwest China, Northeast China, and South China. Participants who were current smokers aged 18-85 years attending clinic for smoking cessation were included. All the participants were treated with 3-month cessation treatment and followed up for 3 months. Data were collected prospectively using online system. The primary outcome was 7-day point abstinence rate at 24 weeks, validated biochemically by an expired carbon monoxide level of less than 10 ppm. The participants lost to follow-up or not providing validation were included as non-abstainers. Findings: A representative sample of 3557 participants were recruited and 2943 participants were included into this analysis. These participants had mean age of 53.05 years, and 94.8% were males, with 75.8% showing symptoms of tobacco dependence. A total of 965 (32.8%) participants were treated with Bupropion + behavioural counselling, followed by 935 (31.8%) with behavioural counselling, 778 (26.4%) with Varenicline + behavioural counselling, 135 (4.6%) with alternative treatments + behavioural counselling, and 130 (4.4%) with nicotine replacement therapy (NRT) + behavioural counselling. After 3-month treatment and 3-month follow-up, 21.74% of the participants quit smoking at 24 weeks. In the multivariable-adjusted analyses, quitting smoking was significantly associated with female, higher socioeconomic status, poor health condition, different treatment received, and less smoking intensity. The tobacco cessation treatment varied widely across different areas of China. In particular, the areas with higher usage of cessation medication were associated with better cessation treatment outcome. Interpretation: The CNTCCS is the first large-scale nationwide cohort study of smoking cessation in China. Rich data collected from this prospective cohort study provided the opportunity to evaluate the clinical practice of tobacco cessation treatment in China. Funding: Chinese Academy of Medical Sciences (CAMS) Initiative for Innovative Medicine (CAMS 2021-I2M-1-010), Heilongjiang Provincial Science and Technology Key Program (2022ZXJ03C02), and National Key R&D Program of China (grant no. 2017YFC1309400).
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OBJECTIVE: To discuss the pathological effect of snoring on pregnant women in Wenzhou area. METHODS: The study was performed between January 2006 and February 2008, 601 women with pregnancies being in clinic or the ward were surveyed about snoring occur, measuring physiological and biochemical parameters in the 13th, 28th week of pregnancy and before delivery, recording the complication and pregnancy outcome. According to their pregnancy and snoring occur, they were divided into the first, the second and the third trimester snoring group and non-snoring group. RESULT: Compared with the non-snoring group, The BMI, abdominal perimeter, the neck circumference and systolic blood pressure in snoring group of every trimester increased significantly (P<0.05). There were no significant differences about the hip circumference of snoring group in the first trimester (P>0.05), but they increased significantly in the second and the third trimester (P<0.05). There were no significant differences about the diastolic blood pressure of snoring group in the first and the second trimester (P>0.05), but they increased significantly in the third trimester (P<0.05). There were no significant differences about the snoring group's BMI, abdominal perimeter, the neck circumference, the hip circumference and blood pressure between the groups of every trimester (P>0.05). Compared with the non-snoring group, the incidence of snoring group's gestational hypertension, premature birth and abdominal delivery increased significantly every trimester of pregnancy (P<0.05). There were no significant differences Between the snoring groups of every trimester (P>0.05). CONCLUSION: The snore makes pregnant women physiological characteristics changed, the incidence of gestational hypertension, premature delivery and abdominal delivery increased. So we should pay more attentions to them in their perinatal stage.
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Complicações na Gravidez , Ronco/epidemiologia , Adulto , Feminino , Humanos , Hipertensão Induzida pela Gravidez/epidemiologia , Incidência , Gravidez , Resultado da Gravidez , Trimestres da Gravidez , Adulto JovemRESUMO
BACKGROUND: Clinicians may fail to make an early diagnosis of pulmonary cryptococcosis (PC) without HIV infection. Serum cryptococcal capsular polysaccharide antigen (CrAg) test, histopathology and culture of lung tissue play different roles in diagnosis of PC. OBJECTIVE: To investigate the performance of serum CrAg test, histopathology and culture of the lung tissue in diagnosis of PC without HIV infection. PATIENTS/METHODS: From January 2011 to September 2017, patients with proven PC were recruited from a teaching hospital in southern China. Those patients with HIV infection, PC confirmed by surgery or PC with probable or possible diagnosis were excluded from the study. Latex agglutination test and CrAg lateral flow assay were used for detection of serum CrAg. Lung biopsy and needle aspiration were performed under computed tomography guidance. RESULTS: Eighty-nine patients with proven PC including 41 male (46.1%) and 48 female (53.9%) were enrolled. Fifty-one (57.3%) patients had underlying disease. Positive CrAg test was found in 83 (93.3%) cases. Among six cases with negative CrAg test, PC was confirmed by histology in two cases and positive culture in four cases. The histopathological results of 77 (86.5%) cases revealed cryptococcal granuloma and 12 cases showed chronic inflammation, which was confirmed by positive culture. Among 65 cases, the diseased tissue of 46 (70.8%) cases presented Cryptococcus neoformans in the culture and one case was diagnosed with lung cancer coexisting with PC. CONCLUSION: Our findings showed that serum CrAg test is rapid and sensitive in diagnosing PC, histology is important for confirming PC and culture plays a complementary role. Biopsied lung tissue should be submitted for cultures whenever feasible.
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The aim of this study was to identify the optimal cut-off value of T cell enzyme-linked immunospot assay for tuberculosis (T-SPOT.TB) and evaluate its diagnostic performance alone (in the peripheral blood) or in combination with the adenosine deaminase (ADA) activity test (in peripheral blood and the pleural fluid) in patients with tuberculous pleurisy.Adult patients presenting with pleural effusion were included in this prospective cohort study. Tuberculous pleurisy was diagnosed by T-SPOT.TB in peripheral blood and a combination of T-SPOT.TB and ADA activity test in pleural fluid and peripheral blood. Receiver operating characteristic (ROC) curve in combination with multivariate logistic regression was used to evaluate the diagnostic performance of the assays.Among a total of 189 patients with suspected tuberculous pleurisy who were prospectively enrolled in this study, 177 patients were validated for inclusion in the final analysis. ROC analysis revealed that the area under the ROC curve (AUC) for T-SPOT.TB in pleural fluid and peripheral blood was 0.918 and 0.881, respectively, and for the ADA activity test in pleural fluid was 0.944. In addition, 95.5 spot-forming cells (SFCs)/2.5â×â10 cells were determined as the optimal cut-off value for T-SPOT.TB in pleural fluid. Parallel combination of T-SPOT.TB and ADA activity test in pleural fluid showed increased sensitivity (96.9%) and specificity (87.5%), whereas serial combination showed increased specificity (97.5%). The combination of 3 assays had the highest sensitivity at 97.9%, with an AUC value of 0.964.T-SPOT.TB in pleural fluid performed better than that in peripheral blood and the ADA activity test in pleural fluid for tuberculous pleurisy diagnosis. The optimal cut-off value of T-SPOT.TB in pleural fluid was 95.5âSFCs/2.5â×â10 cells. Combination of 3 assays might be a promising approach for tuberculous pleurisy diagnosis.
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Adenosina Desaminase/imunologia , ELISPOT/métodos , Interferon gama/imunologia , Tuberculose Pleural/diagnóstico , Tuberculose Pleural/imunologia , Adulto , Idoso , ELISPOT/normas , Feminino , Testes Hematológicos , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pleural/imunologia , Estudos Prospectivos , Curva ROC , Valores de Referência , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: To evaluate the effects of lupus anticoagulant (LA) on pulmonary thromboembolism (PTE). METHODS: Thirty-eight patients with PTE (17 massive and 21 submassive) and 30 healthy adults were studied. Russell's viper venom time (RVVT) was used to examine the ratio of LA (LAR), and a colorimetric method was used to detect the activity of plasma protein C (PC:A) and radioimmunoassay (RIA) was employed to measure the level of plasma thromboxane B(2) (TXB(2)) and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha). RESULTS: Compared with the normal group, LAR, TXB(2) and TXB(2)/6-keto-PGF1alpha showed significant increase in the massive PTE and the submassive PTE groups (P < 0.01), and the levels were higher in the massive group than in the submassive group (P < 0.01). Both groups showed significant decrease in PC:A and 6-keto-PGF1alpha compared with the normal group (P < 0.01). CONCLUSIONS: LA can increase TXB(2)/6-keto-PGF1alpha and decrease PC:A in patients with PTE. It is suggested that there may be an association between the increase of LAR and the presence of PTE.
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6-Cetoprostaglandina F1 alfa/sangue , Proteína C-Reativa/análise , Inibidor de Coagulação do Lúpus/sangue , Embolia Pulmonar/sangue , Tromboxano B2/sangue , Adulto , Feminino , Humanos , Inibidor de Coagulação do Lúpus/fisiologia , Masculino , Pessoa de Meia-Idade , Prostaglandinas/sangue , Embolia Pulmonar/etiologia , Embolia Pulmonar/patologia , Radioimunoensaio , Tromboembolia/prevenção & controleRESUMO
OBJECTIVE: To study the preventive effect of Breviscapus Injection on the chronic hypoxic myocardium injury in rats and its mechanism. METHODS: Transmission electron microscope and biochemical analysis were used to assay the therapeutic effect of Breviscapus Injection in rat model induced by 4 week's hypoxia. RESULTS: The contents of malondialdehyde (MDA) and Ca(2+) in the homogenate of myocardial tissue of the hypoxic rats were significantly higher than those of the control rats. The activities of superoxide dismutase (SOD), nitric oxide synthase (NOS) in the homogenate of myocardial tissue and the plasmic NO levels of the hypoxic rats were significantly lower than those of the control rats. Breviscapus Injection reduced the contents of MDA and Ca(2+), and increased the levels of SOD, NOS and NO. Ultrastructural examination revealed that the injuries of the ultrastructure of heart in hypoxic rats were improved by treatment with Breviscapus Injection. CONCLUSION: Breviscapus Injection can effectively prevent and treat the hypoxia-induced myocardial damage. One of its mechanisms may relate to its adjusting NO level, anti-damaging of free radicals and inhibiting calcium overload.
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Asteraceae , Coração/efeitos dos fármacos , Hipóxia/tratamento farmacológico , Plantas Medicinais , Animais , Cálcio/metabolismo , Doença Crônica , Hipóxia/metabolismo , Hipóxia/patologia , Injeções , Masculino , Malondialdeído/análise , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Óxido Nítrico/sangue , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismoRESUMO
The objective was to investigate the molecular mechanism of mitochondrial reactive oxygen species (ROS) signaling regulation of pulmonary artery endothelial cell (HPAEC) secretion in the condition of oxidative stress. Acrolein (40 µM) induced HPAEC mitochondrial generation of ROS, rotenone (2 µmol/L) blocked mitochondrial respiratory chain complex I, cesium chloride (CsCl, 40 mmol/L)blocked K(+)channels, and saline (0.9 g/dl) were used as control. The generations of NOS, ET-1 and VEGF were determined with ELISA in the condition of different treatment reagents namely acrolein, acrolein plus rotenone, acrolein plus CsCl and saline. In the different reagent treatment of HPAECs, acrolein increased mitochondrial ROS, membrane potential, Kv1.5 mRNA and protein expression, intracellular calcium and the generation of NOS (determining NO production), ET-1 and VEGF, and those were reduced by rotenone. CsCl decreased the increment of membrane potential, the elevation of intracellular calcium and the upregulation of NOS, E-1 and VEGF expressions, which were induced by acrolein. The present study demonstrated that mitochondrial ROS-K(+)channel regulated HPAEC secretion of NO, ET-1 and VEGF in the condition of oxidative stress. Kv1.5 channel may be an important component of ROS-K+ channel signaling pathway, and intracellular calcium contributed to mitochondrial ROS-K(+) channel signaling modulation of HPAEC secretion.
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Endotélio Vascular/metabolismo , Canal de Potássio Kv1.5/metabolismo , Mitocôndrias/metabolismo , Artéria Pulmonar/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Acroleína/farmacologia , Western Blotting , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Endotelina-1/genética , Endotelina-1/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Humanos , Peróxido de Hidrogênio/metabolismo , Canal de Potássio Kv1.5/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Artéria Pulmonar/citologia , Artéria Pulmonar/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotenona/farmacologia , Desacopladores/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: To study the effect of celecoxib on chronic hypoxia and hypercapnic pulmonary hypertension. METHODS: SD rats were randomly divided into normal control group (A), hypoxic hypercapnic group (B), hypoxic hypercapnia+ celecoxib group (C). The content of TXB2 and 6-keto-PGF1alpha in plasma and lung were detected by the technique of radioimmunology. RESULTS: (1) Mean pulmonary arteria pressure(mPAP) was significantly higher in rats of B group than those of A group. mPAP was significantly higher in rats of C group than those of B group. Differences of mPAP were not significant in three groups. (2) The content of TXB2 in plasma and lung and the ratio of TXB2/6-keto-PGF1alpha were significantly higher in rats of B group than those of A group. The ratio of TXB2/6-keto-PGF1alpha was significantly higher and the content of 6-keto-PGF1alpha in plasma and lung was significantly lower in rats of C group than those of B group. (3) Light microscopy showed that WA/TA (vessel wall area/total area) and PAMT (the thickness of medial smooth cell layer) were significantly higher in rats of B group than those of A group. WA/TA and PAMT were significantly higher in rats of C group than those of B group. (4) Electron microscopy showed the thickening of vessel wall and the proliferation of collagen fiber in B group and augmentation of smooth muscle cell and abundance of myofilament in pulmonary arterioles in C group. CONCLUSION: Celecoxib can aggravate hypoxic hypercapnia pulmonary hypertension and pulmonary vessel remodeling by increasing the ratio of TXA2/PGI2.
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Hipercapnia/complicações , Hipertensão Pulmonar/fisiopatologia , Hipóxia/complicações , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Animais , Celecoxib , Doença Crônica , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Epoprostenol/sangue , Hipertensão Pulmonar/etiologia , Masculino , Pirazóis/efeitos adversos , Ratos , Ratos Sprague-Dawley , Sulfonamidas/efeitos adversos , Tromboxano A2/sangueRESUMO
OBJECTIVE: To reseach the correlations between cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) expressions and angiogenesis in pharyngeal tissue of patients with obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Biopsies were obtained by uvulopalatopharyngoplasty from 40 patients with mild to severe OSAHS. Control specimens of palatopharyngeal and palatoglossal arch mucosa were retreved from 6 patients with chronic tonsillitis and proved have no related disorders. HE was used to observe the changes of pharyngeal tissue, immunohistochemical staining with antibodies against COX-2, VEGF, microvessel density (MVD) (marked with CD34). RESULTS: COX-2 and VEGF mainly expressed at pavement-epithelium and glandular epithelium of pharyngeal tissue, and stronger COX-2 and VEGF expression was found in midrange and severe OSAHS than mild and control group (P < 0.01), so as MVD. COX-2 expression was correlated positively with VEGF expression, and had significant correlation with MVD. VEGF expression had the same correlation with MVD. These three targets had considerable relation with apnea hypopnea index (AHI) and lowest O2 saturation at night. CONCLUSION: There was angiogenesis which had important relationship with hypoxia degree in patients of OSAHS, and COX-2 and VEGF play a crucial role in its development.
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Ciclo-Oxigenase 2/metabolismo , Neovascularização Patológica , Faringe/metabolismo , Apneia Obstrutiva do Sono/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Ciclo-Oxigenase 2/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Faringe/irrigação sanguínea , Apneia Obstrutiva do Sono/metabolismo , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
AIM: To study the effect of Safflower injection (a compound of Chinese Traditional medicine) on pulmonary hypertension in rat during chronic hypoxia and hypercapnia. METHODS: Sprague-Dawley rats were randomly divided into normal control group (A), hypoxic hypercapnic group (B), hypoxic hypercapnia + Safflower injection group (C). The concentration of TXB2 and 6-keto-PGF18 in plasma and in lung homogenate were detected by the radioimmunoassay. RESULTS: (1) mPAP, weight ratio of right ventricle (RV) to left ventricle plus septum (LV + S) were much higher in rats of hypoxic hypercapnic group than those of control group. Differences of mCAP among the three groups were not significant. (2) The concentration of TXB2 and the ratio of TXB2/6-keto-PGF1a were significantly higher in rats of B group than those of A and C group. (3) The results examined by light microscopy showed that WA/TA (vessel wall area/total area), SMC (the density of medial smooth muscle cell) and PAMT (the thickness of medial smooth cell layer) were significantly higher in rats of B group than those of A and C group. (4) The results examined by electron microscopy showed proliferation of medial smooth muscle cells and collagen fibers of pulmonary arterioles in rats of B group, and Safflower injection could reverse the changes mentioned above. CONCLUSION: Safflower injection may inhibit hypoxic hypercapnia pulmonary hypertension and pulmonary vessel remodeling by decreasing the ratio of TXB2/6-keto-PGF1a.
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Carthamus tinctorius/química , Medicamentos de Ervas Chinesas/farmacologia , Hipercapnia/fisiopatologia , Hipertensão Pulmonar/prevenção & controle , Hipóxia/fisiopatologia , 6-Cetoprostaglandina F1 alfa/metabolismo , Animais , Hipercapnia/metabolismo , Hipercapnia/patologia , Hipóxia/metabolismo , Hipóxia/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Tromboxano B2/metabolismoRESUMO
AIM: To investigate the effect of protein kinase C regulating pulmonary arterial remodeling in chronic hypoxic rats. METHODS: Electron microscope, radioactivity, immunohistochemistry and image analyser were used. RESULTS: (1) Mean pulmonary arterial pressure (mPAP) and weight ratio of RV to LV + S were significantly higher than that of control group (P < 0.01). (2) WA/TA and SMC were significantly higher than that of control group (P < 0.01). Electron microscopy showed the proliferation of smooth muscle cells and the disposition of collagenous fiber in pulmonary arterioles induced by hypoxia. (3) The total, cytosolic, particulate fraction PKC activity and the ratio of particulate fraction to total PKC activity were significantly higher than that of control group (P < 0.01). (4) Expression of PKC, collagen I were significantly higher than that of control group (P < 0.01), the difference of collagen III was not significant between two groups (P > 0.05). (5) There were good correlation between the total, particulate fraction PKC activity, the ratio of particulate fraction to total PKC activity, expression of PKC and SMC, collagen I in pulmonary arterioles. CONCLUSION: The PKC regulates the proliferation of pulmonary artery smooth muscle cells and expression of pulmonary arterial collagen in chronic hypoxic rats, which may play an important role in the pathogenesis of pulmonary hypertension and structural remodeling of pulmonary arteries.