Pancreatic polypeptide: a review of its involvement in neuro-endocrine reflexes, islet-acinar interactions and ethanol-evoked physiopatologic pancreatic gland changes.

prevents, in pancreocytes, the evolving of a "supramaximalecbolic-stimulation" process. The PP involvement as a modulating agent of pancreon's reactivity is reflected by the progressive increment of its plasma values in the first week of an evolving AP episode. In the AP associated to a large meal, an overpowering of the pancreon's brake might have a pivotal role. In experimental and clinical chronic alcoholism, a vagal neuropathy of the Pavlov inhibitory fibers that, as a consequence, impairs the pancreon's brake through a depression of PP secretion is at the basis of an enhanced reactivity of the duodeno-pancreatic reflexes. The latter leads to intrapancreatic cholinergic hypertonus and to Vater papilla's dysfunction. These changes, plus an enhanced pancreocyte's response to CCK, are at the core of acinar cell "supramaximal stimulation" with the organelle disruption that process implies. The intrapancreatic cholinergic hypertonus, the enhanced exocrine cell reactivity to CCK stimulation, and the augmented resistance to the pancreatic secretion flow at Oddi sphincter, explain the aggravating influence of chronic alcoholism on an episode of acute biliary pancreatitis. As the PP secretion, normally elicited by secretin, CCK, food and insulin hypoglycemia, is depressed in the presence of an augmented number of PP cells, as it is in the cases of chronic alcoholics, cystic fibrosis patients and, also, in dogs with pancreatic fibrosis (ductal ligation), it has been inferred, besides our postulated impairment of the Pavlov inhibitory fibers in the vagus nerves, that the defect of PP release is localized to the common final pathway of the above stimuli, probably in or near the PP cell itself This review was prompted by the unexpected experimental finding in canines that Tissucol-induced pancreatic ductal blockade elicits Pancreatic Polypeptide (PP) release and seems to be at the basis of the beneficial effects on taurocho- late-induced acute pancreatitis (AP). In the release mechanism of this regulatory peptide secreted by PP cells located in the periphery of Langerhans islets and scattered in the ductal epithelium, two neuroendocrine reflexes (NER) are involved. The "short" NER is evoked from the duodenum by an unknown component of bile-pancreatic secretion. The "long" NER is triggered by a vagovagal reflex. PP induces a depression of the intrapancreatic cholinergic tone. On the one hand suppressing, hormonally, nervous impulses discharge from the vagal nuclear complex in the brainstem. On the other, interfering paracrinically on the cholinergic transmission by acting, presynaptically, on post-ganglionic cholinergic neurons. The resulting PP-evoked fall of the intrapancreatic cholinergic tone depresses the hormone induced (secretin, CCK) pancreons secretory response. PP, with other agents, contributes to the "fail-safe" system or pancreon's brake that

Niveles séricos de ceruloplasmina y mieloperoxidasa en pacientes con enfermedad coronaria crónica / Serum levels of ceruloplasmin and myeloperoxidase in patients with stable coronary artery disease / Níveis séricos de ceruloplasmina e mieloperoxidase em pacientes com doença coronariana crônica

La ceruloplasmina (CP) es una proteína que participa en el metabolismo del hierro y transporta el 95% del cobre plasmático. Se considera un inhibidor fisiológico de la mieloperoxidasa (MPO), enzima leucocitaria que forma parte del sistema inmune innato. Ambas se postulan como biomarcadores de la enfermedad cardiovascular. El objetivo del presente trabajo fue determinar la actividad de CP y la concentración de MPO en pacientes con enfermedad coronaria crónica (ECC) y analizar su asociación con otros parámetros de inflamación. Se estudiaron 22 pacientes con ECC y 22 controles sanos. La actividad de CP fue determinada por el método de Ozcan Erel y las concentraciones de MPO, proteína C- reactiva ultrasensible (PCR-us) e Interleuquina 6 (IL-6) por métodos estandarizados. La concentración de MPO y la actividad de CP fueron mayores en pacientes con ECC que en sujetos sanos; (417±295 vs. 179±145 ng/mL, p=0,0018); (891±179 vs. 630±115 IU/L, p< 0,0001) respectivamente y la asociación entre las variables fue estadísticamente significativa (r=0,47, p=0,0272). La liberación sistémica de MPO que conduce a valores incrementados de su concentración sérica, y la hiperceruloplasminemia podrían considerarse un rasgo característico de ECC asintomática e indicarían aterosclerosis en pacientes que eventualmente desarrollen ECC.

Streptozotocin-induced diabetes, bile-pancreatic secretion and insulo-pancreon-axis interaction.

The present tests were undertaken in order to analyze in male Wistar rats the changes in the exocrine and endocrine pancreas and on the interactions that normally evolve in the insulo-pancreon-axis. To evaluate this by a single i.p. Boots secretin injection, glycemia (G), amylasemia (A) and lipasemia (L) were determined. In bile-pancreatic secretion, we analyzed, pre and post-secretin, the following parameters: volume (V), bicarbonate output (BO), amylase output (AO) and lipase output (LO). Three groups of tests were done: a) control (C); b) streptozotocin-treated non-diabetic-rats (St-ND) and c) streptozotocin-treated diabetic animals (St-D) which showed morning glycemia values higher than 16.0 mmol/l. Four months later, under Tiopental i.p anesthesia, a bile-pancreatic fistula was done. Following a 30 min basal period, Boots secretin (20 CU/kg) was i.p injected. Bile-pancreatic secretion put in evidence a significant fall of BO in both St-ND and St-D series. In controls, AO revealed a post-secretin increase of 160%, while in the St-D rats showed a depression of 41%. The behavior of L was different, being augmented (+27%) in the C, while in the St-D rats the response was significantly higher (+95%). In bile-pancreatic-secretion, the fall of BO and AO in the St-ND and St-D series in respect to the C, are probably consequence of the diminishing potentiating effects exerted normally by insulin on the secretin-induced water and bicarbonate secretion of the pancreon units. In contrast, the rising of LO in the St-D, an expression of an enhancing pancreocyte's synthesis and secretion of lipase. The blood changes of A (depression) and of L (increase) in respect to the C values, although without reaching significant level, mirror those observed in bile-pancreatic secretion.

Streptozotocin-induced diabetes, bile-pancreatic secretion and insulo-pancreon-axis interaction / Streptozotocin-induced diabetes, bile-pancreatic secretion and insulo-pancreon-axis interaction.

The present tests were undertaken in order to analyze in male Wistar rats the changes in the exocrine and endocrine pancreas and on the interactions that normally evolve in the insulo-pancreon-axis. To evaluate this by a single i.p. Boots secretin injection, glycemia (G), amylasemia (A) and lipasemia (L) were determined. In bile-pancreatic secretion, we analyzed, pre and post-secretin, the following parameters: volume (V), bicarbonate output (BO), amylase output (AO) and lipase output (LO). Three groups of tests were done: a) control (C); b) streptozotocin-treated non-diabetic-rats (St-ND) and c) streptozotocin-treated diabetic animals (St-D) which showed morning glycemia values higher than 16.0 mmol/l. Four months later, under Tiopental i.p anesthesia, a bile-pancreatic fistula was done. Following a 30 min basal period, Boots secretin (20 CU/kg) was i.p injected. Bile-pancreatic secretion put in evidence a significant fall of BO in both St-ND and St-D series. In controls, AO revealed a post-secretin increase of 160

, while in the St-D rats showed a depression of 41

. The behavior of L was different, being augmented (+27

) in the C, while in the St-D rats the response was significantly higher (+95

). In bile-pancreatic-secretion, the fall of BO and AO in the St-ND and St-D series in respect to the C, are probably consequence of the diminishing potentiating effects exerted normally by insulin on the secretin-induced water and bicarbonate secretion of the pancreon units. In contrast, the rising of LO in the St-D, an expression of an enhancing pancreocyte’s synthesis and secretion of lipase. The blood changes of A (depression) and of L (increase) in respect to the C values, although without reaching significant level, mirror those observed in bile-pancreatic secretion.

Variabilidad biológica de aldolasa sérica: su utilidad en la interpretación de los resultados / Biological variation of serum aldolase: its use for interpretation of the results / Variabilidade biológica de aldolase sérica: sua utilidade na interpretagáo dos resultados

El objetivo de este trabajo fue determinar la variabilidad biológica (VB) de Aldolasa (ALD) en individuos sanos, el índice de individualidad (II) del analito y evaluar la utilidad del intervalo de referencia poblacional (IRP) considerando al IRP de los analitos útil cuando el II es > 1,4 y de poca utilidad si es <0,6. También se evaluó el valor de referencia para el cambio (VRC) en la interpretación de dos determinaciones seriadas del mismo individuo, especialmente en el seguimiento de enfermedades músculo-esqueléticas en las que los niveles de creatinquinasa (CK) permanecen dentro del intervalo de referencia, mientras que los de ALD están elevados. Se obtuvieron 8 muestras de sangre de 10 individuos aparentemente sanos en días diferentes según protocolo preestablecido. Se determinó la actividad de ALD por método enzimático UV y se calcularon los parámetros de VB, II y VRC. Se obtuvo una VB intraindividual: 31%; VB interindividual: 21%, II 1.47 y VRC 90%. De acuerdo a los coeficientes de VB y el II obtenidos, los IRP son útiles para la interpretación de los resultados de ALD. Un resultado seriado será estadísticamente diferente del dato previo cuando el mismo tenga una diferencia mayor al 90% en relación al valor previo. El VRC entre dos determinaciones seriadas debe ser calculado en cada laboratorio con su propia variabilidad analítica para una correcta interpretación de los resultados.

The aim of this study was to determine the Biological Variation (BV) of Aldolase (ALD) in healthy patients, the individuality index (II) of the analyte and to assess how useful the population reference interval (PRI) is for the interpretation of the results, considering PRI useful when the II is >1.40 and useless when it is <0.6. Reference change values (RCV) were also assessed in the interpretation of two serial measurements of the same individual, specially in the monitoring of patients in which the serum level of Creatine Kinase (CK) remain within the reference range while ALD values are increased. Eight bloodsam-ples were obtained from ten apparently healthy subjects in different days according to a predetermined protocol. ALD activity was measured by an enzymatic UV method and BV, II and RCV were calculated. Intraindividual BV was 31 %, interindividual BV 21 %, II 1.47 and RCV 90%. Based on the results obtained for BV and II, PRIs are useful for the interpretation of ADL results. A serial result will be statistically different from the previous one when the variability between both results is higher than 90%. RCV must be determined in each laboratory using their own analytical variability in order to obtain a correct interpretation of the results.

O objetivo deste trabalho foi determinar a variabilidade biológica (VB) de Aldolase (ALD) em individuos saudáveis, o índice de individualidade (II) do analito e avaliar a utilidade do intervalo de referencia populacional (IRP) considerando o IRP dos analitos útil quando o II é > 1,4 e de pouca utilidade se é <0,6. Também foi avaliado o valor de referencia da variagáo (VRV) na interpretagáo de duas determinagóes seriadas do mesmo individuo, especialmente no seguimento de doengas músculo-esqueléticas nas quais os níveis de creatinoquinase (CK) permanecem dentro do intervalo de referencia, enquanto que os de ALD estáo elevados. Foram obtidas 8 amostras de sangue de 10 individuos aparentemente saudáveis em dias diferentes conforme protocolo preestabelecido. Determinou-se a atividade de ALD por método enzimático UV e se calcularam os parámetros de VB, II e VRC. Foi obtida uma VB intra-individual: 31 %; VB interindividual: 21 %, II 1.47 e VRV 90%. De acordo com os coeficientes de VB e o II obtidos, os IRP sáo úteis para a interpretagáo dos resultados de ALD. Um resultado seriado será estatisticamente diferente do dado prévio quando o mesmo tenha uma diferenga maior a 90% em relagáo ao valor prévio. O VRV entre duas determinagóes seriadas deve ser calculado em cada laboratório com sua própria variabilidade analítica para uma correta interpretagáo dos resultados.

Pancreatitis y pancreatopatía crónica: evaluación fisiopatogénica, clínica y funcional: (basada en 1.300 casos en más de tres décadas en el Hospital de Clínicas de Bs. As.) / Chronic pancreatitis and chronic pancreatopathy: physiopathogenic, clinical and funcitonal evaluation. experience with 1,300 cases during three decades

Siguiendo a una experiencia de 33 años, de orden clínico y funcional (test de secretina), se intenta, por una parte, precisar los conceptos de pancreatitis crónica (PC) y de pancretopatía crónica (Pt.p.Cr.). Por otra, de consignar los índices de incidencia y de sus peculiaridades clínicas de expresión. El término de PC se propone cuando: "Las alteraciones estructurales del páncreas, con las eventuales modificaciones de los órganos y elementos anatómicos que con él se vinculan, y/o el déficit funcional de su componente exocrino ("pancreón") constituyen la fuente de la expresión clínica que predomina, de manera ostensible, en el complejo sindromático que exhibe el paciente en evaluación". Se estima como no ajustada a la realidad la noción clásica que considera a la PC como una afección de curso progresivo inexorable. Se enfatiza, por el contrario, la noción de que la PC cuando es adecuadamente tratada puede detener su evolución e, incluso, mostrar evidencias clínico-funcionales de su capacidad regenerativa. La denominación de pancreatopatía crónica (Pt.p.Cr.) es propuesta para aquellas condiciones en las que: "Los signos y/o síntomas originados por eventuales alteraciones anátomos-estructurales del páncreas y/o por modificaciones funcionales de su componenete secretorio exocrino se hallan disimuladamente inmersos dentro de un complejo sindromático que tiene génesis extra-pancreonal". De los 1.300 tests de secretina efectuados, 100 fueron dedicados a perfilar la respuesta secretoria exocrina normal. Y ello tanto en el hombre como en la mujer, discriminando, además, en ambos sexos, los resultados obtenidos por encima y por debajo de una edad crítica límite trazada a los 45 años. En 368 casos, la evaluación conjunta clínica-funcional permitió incluir a los pacientes dentro de la categoría de las PC. Dentro de esta entidad nosológica, se hizo el distingo entre la PC calcificante (alcohólica e idiopática), la autoinmune y la obstructiva. Como PC alchólica fueron.

Following a clinical evaluation and an exocrine pancreatic secretion exploration with the secretin test for more than three decades, we have tried to delineate the concepts of chronic pancreatitis (CP) and chronic pancreatopathy (Chr. Ptp). Besides, the rate of incidence of these two clinical entities in the Clinicas Hospital of Bs. As. was analyzed and discussed. The term CP was accepted when: "The anatomo-structural changes of the pancreatic gland and/or the exocrine functional component impairment constitute the patient's dominant clinical expresion". It is considered as erroneous and misleading the assumption that considers CP as a disease of an inexorable progressive course. On the contrary, the authors empehasize their conviction, based on experimental and clinical experiences, that CP is susceptible, when appropriately treated, of stopping its evolution and even disclose clinical-functional imporovements testifyng the inherent regenerative capacity of the gland. In contrast to the above, the denomination of Chr.Ptp. should be restricted when: "The signs and/or symptoms induced by the anatomo-structural changes of the pancretic gland and/or the functional derangement of the exocrine component remain disguised in the clinical syndrome of other diseases". Out of the 1,300 secretin tests performed, 100 were done on healthy controls. This study allowed establishing the normal statistical values of the different parameters. Besides, of showing the differences between men and women, especially above the critical age of 45. This clinical-functional evaluation allowed classifying 368 cases as CP. The folowing sub-groups were delineated: Calcifyiung "CP" (alcoholic, 240 cases and idiopathic, 119 cases); autoimmune CP (n=7) and Obstructive "CP" (n=11). In the Chr.Ptp. entity were classified 171 cases. As it is implied in the definition, this type of chronic inflammation of the pancreatic gland remained immersed in other disease entities.

[Biochemical profile of the pancreatic function: pancreolauril and oral glucose tolerance tests]. / Evaluación bioquímica de la función pancreática: Pruebas del pancreolauril y de la tolerancia a la glucosa oral.

BACKGROUND: The pancreas is a mixed gland that takes part in the digestion of nutrients and in the homeostasis ofglycemia. Chronic pancreopathy is the cause of secretory insufficiency, characterized by an inflammatory process that leads to fibrosis of the pancreas, with a progressive loss of both exocrine and endocrine functions of the gland. OBJECTIVE: To study both the exocrine and endocrine pancreatic relationship in patients with pancreatopathies and other non-pancreatic digestive alterations, by means of serum pancreolauril (sPL) and oral glucose tolerance tests (OGTT). Glycemia and insulin, basal and at 30, 60 and 120 minutes; amylase and lipase; and the HOMA index (homeostatic model) were determined in serum. MATERIAL AND METHODS: Thirty-two patients were evaluated: normal OGTT (n=11, control group) and pathologic OGTT (n=21). From the latter group, a subgroup (n=11) with a diagnosis of chronic pancreatitis (CP) was studied. RESULTS: Patients with pathologic OGTT in relation with normal OGTT presented a significant increase of glycemia at the four periods of time and of insulin at 120 minutes (P < 0.05), and a significant decrease of sPL (P < 0.05). In patients with CP, men were more than women, and all of them presented a pathologic OGTT and the sPL was significantly lower (P < 0.001). CONCLUSION: By the biochemical tests used, pancreas functionality corresponds with a close relationship between exocrine and endocrine pancreas. Thus, we suggest the use of the sPL test as a helpful tool for the diagnosis of CP.

Utilidad de la fosfatasa alcalina urinaria como marcador precoz de lesión tubular renal / Utility of urinary alkaline phosphatase as early marker of renal tubular failure

El objetivo de este estudio fue determinar la actividad de la fosfatasa alcalina urinaria (FALur) para evaluar precozmente lesión tubular y su utilidad diagnóstica. Los pacientes estudiados fueron: 20 Controles (C), 11 hipertensos (HTA), 23 diabéticos (DBT) y 34 con insuficiencia renal de diverso origen (IRDO). Se realizaron las determinaciones de: creatinina, clearence de creatinina (Jaffé cinético), FAL sérica y urinaria (cinético DGKC), microalbuminuria (inmunoturbidimétrico), proteiunuria (turbidimétrico), uroproteinograma, SDS-PAGE (al 12,5%) e isoenzimograma de FAL. La FAL sérica hallada fue normal, sin diferencia entre grupos y sin relación con el aumento de la FALur. El valor de corte recomendado para FALur fue de 8 UI/L. La FALur estuvo elevada en HTA e IRDO y normal en individuos con DBT. Los aumentos de FALur en IRDO se relacionaron con la lesión tubular estructural y en pacientes con HTA podrían relacionarse con alteración tubular precoz. Se propone la determinación de FALur para la detección temprana de lesión tubular ante falla renal establecida o en individuos con riesgo de desarrollarla, y se establece su utilidad en pacientes: - con DBT y HTA para seguimiento (junto a microalbuminuria y clearence de creatinina), - internados en riesgo de insuficiencia renal aguda: para orientar tratamientos, - con insuficiencia renal crónica: como indicador de lesión y pronóstico.

The objective of this study was to determine the activity of urinary Alkaline Phosphatase (ALPur) to evaluate early tubular failure and its diagnostic usefulness. The patients studied were: 20 Controls (C), 11 with Hipertensión (HTA), 23 Diabetic (DBT) and 34 with renal Insufficiency of diverse origin (IRDO). The creatinine, creatinine clearence (kinetic Jaffé) serum and urinary ALP (kinetic DGKC), microalbuminuria (Immunoturbidimetric), proteiunuria (Turbidimetric), uroproteinogram, SDS-PAGE (12.5%) and ALP isoenzymes determinations were made. The results indicate that serum ALP was normal, without difference between groups, and no relation with the increase in ALPur. Recommended cut-off value of ALPur was 8 UI/L. ALPur was elevated in HTA and IRDO, and normal in DBT. Increases in ALPur in IRDO were related to the structural tubular injury, and those in HTA could be related to early tubular alteration. Determination of ALPur is proposed for early detection of tubular injury, before renal failure is established or when there is risk of developing it, establishing its usefulness in: - DBT and HTA patients: screening (together with microalbuminuria and creatinine clearence). - Hospitalized patients in risk of acute renal insufficiency: in order to orient treatments. - Patients with chronic renal insufficiency: as an indicator of injury and prognosis.

Estabilidad de muestras conservadas en tubo primario: un estudio de 25 analitos de química clínica / Stability of specimens stored in primary tube: a study on 25 analytes of clinical chemistry

Se estudió la estabilidad de veinticinco analitos conservados durante siete días en dos tipos de tubos primarios: tubos de polimetilmetaacrilato (PMMA) con gránulos y tubos con gel separador, ambos con acelerador de la coagulación. El objetivo fue determinar en qué tubo los analitos tenían mayor estabilidad y como consecuencia, cuánto tiempo podían conservarse las muestras en ambos tubos. Las muestras fueron conservadas en el tubo primario a 4-8 ºC y se analizaron por duplicado diariamente durante siete días. La estabilidad de los analitos se determinó comparando los resultados de los siete días con los valores obtenidos el primer día y los límites de aceptabilidad derivaron del coeficiente de variación (CV) de cada determinación, de la variabilidad biológica (VB) intraindividual y de un análisis multivariado de varianza MANOVA. Los promedios de aldolasa, fósforo, glucosa, lactatodehidrogenasa, potasio y sodio cuando la muestra se conservó con gránulos, tuvieron diferencias estadísticamente significativas al compararlos con los promedios de los mismos analitos conservados en gel; resultados similares se obtuvieron cuando se tomó como límite de aceptabilidad el CV y la VB intraindividual. Cada laboratorio debería establecer la estabilidad de sus analitos según el tubo primario utilizado, con el objetivo de responder a no conformidades que requieran el procesamiento de analitos sobre muestras previamente extraídas en el caso de que éstas se conserven en tubo primario.

The stability of 25 analytes during a seven-day storage in two different kinds of tubes was studied. PMMA (polimetilmetaacrilate) tubes contain a clotting activator (glass particles) and the other tubes contain a gel barrier. The aim was to determine the analytes' stability in both kinds of tubes and, as a consequence, to determine the optimal time for storage of the samples in the primary tube. The specimens were maintained at 4-8 ºC and analyzed in duplicate during seven days. The analytes' stability was determined by comparing the results obtained each day with those obtained on the first day. The significant change limits were based on the determination of the variation coefficient, on the biological variation and on statistically significant changes using a MANOVA test. Mean values of aldolasa, phosphate, glucose, lactic dehydrogenase, potassium and sodium stored in tubes with a clotting activator had statistical differences in comparison with the mean values of the same analytes stored with a gel barrier. Each laboratory should investigate the specific analytes' stability according to the collection device used.

Ceruloplasmina: determinación de su actividad ferroxidasa / Ceruloplasmin: measurement of serum ferroxidase activity

La Ceruloplasmina (Cp) es la principal proteína transportadora de cobre en circulación. Su concentración es abundante en plasma; se considera un reactante de fase aguda y su función fisiológica no se encuentra fehacientemente establecida. Fundamentalmente se sintetiza en los hepatocitos. También se encuentra en otros tipos celulares como monocitos, astrocitos y células de Sertoli. Su concentración sérica se utiliza en el diagnóstico diferencial de enfermedad de Wilson. La concentración total en plasma se considera igual a la suma de las concentraciones de apo y holo Cp, de manera que la cantidad de esta proteína determinada por un método inmunológico no indica que la enzima se encuentre presente solamente en su forma activa. Entonces, al utilizar esta metodología, se sobreestima la proteína funcionalmente activa. Existen diversos métodos para determinar su actividad. En este trabajo se describe un método automatizado para medir su actividad ferroxidasa que utiliza iones Fe2+ como sustrato. Los valores de referencia de actividad de Cp se diferenciaron estadísticamente entre el grupo de mujeres y el de hombres, siendo de 424-796 UI/L y 397-733 UI/L, respectivamente. Además, se obtuvo una correlación significativa entre la actividad ferroxidasa y la concentración proteica (r=0,7285; p<0,0001).

Ceruloplasmin (Cp) is the principal copper carrier in human plasma. It is an abundant protein that participates in the acute phase reaction to stress, but its physiological function is unknown. Althought Cp is synthesised predominantly in the liver, other cell types express the protein, including monocytes, astrocytes and Sertoli cells. The serum concentration of the copper protein ceruloplasmin has been an important diagnostic indicator of Wilson`s disease. Measurement of the total amount of Cp protein may not reflect Cp enzyme activity in the serum. The immunologic assay may lead to overestimation of the total amount of functional Cp in the serum due to this method's capacity to determine both the functional holo Cp and non-functional apo Cp. Several methods for determining ferroxidase activity have been reported. In this study, a method is described for automated measurement of the activity. In this method, Fe2+ ions are used as the substrate. The range for serum Cp ferroxidase activity in healthy persons was 424-796 UI/L for women, and 397-733 UI/L for men. Significant correlations between serum ferroxidase activity and Cp concentration (r=0,7285; p < 0,0001) were found.

Influence of hydrocortisone, prednisolone, and NO association on the evolution of acute pancreatitis.

Leukocyte activation, inflammatory up-regulation, and microcirculatory disruption associated with ischemia-reperfusion injury are hallmarks in the pathogenesis of acute pancreatitis (AP). NO donors ensure microvascular integrity, while glucocorticoids act as anti-inflammatory and immune modulator drugs. AP was induced by the biliopancreatic duct outlet exclusion-closed duodenal loops (BPDOE-CDLs) model. Treatment with hydrocortisone (6 mg/kg) or prednisolone (0.5 mg/kg) alone or together with DETA-NO (0.5 mg/kg) was done (a)1 hr pre or (b)1 hr post, or (c) 1 hr pre and 4 hr post ,or (d) 4 hr post triggering AP. NOS inhibition by L-NAME (15 mg/kg) and glucocorticoid receptor blockage by mifepristone (3 mg/kg) was considered. AP severity was assessed by biochemical and histopathological analyses. Treatment with glucocorticoids together with DETA-NO 1 hr pre and 4 hr post BPDOE-CDLs reduced serum amylase, lipase, C-reactive protein, IL-6, IL-10, hsp72, and 8-isoprostane as well as pancreatic and lung myeloperoxidase. Acinar and fat necrosis, hemorrhage, and neutrophil infiltrate were also decreased. Hydrocortisone together with DETA-NO rendered the best results. We conclude that AP severity was significantly diminished by glucocorticoids associated with DETA-NO, with the optimal dose and time point of administration being crucial to provide adequate protection against AP.

Lipasa: una enzima singular por sus interacciones neuro-hormonales. (Revisión y análisis experimental y clínico) / Lipase: a particular enzyme because of its neuro-hormonal interactions

Un objetivo de esta presentación es el de analizar las peculiaridades distintivas de la enzima lipasa proveniente de diferentes fuentes: gástrica (LG), intestinal (LI)hepática (LH), lipoproteica (LLP), pero, en especial, aquella de la pancreática (LP), sobre todo en lo relativo a sus interacciones neuro-hormonales.

Relaxin prevents the development of severe acute pancreatitis.

AIM: To investigate the severity of acute pancreatitis (AP) is associated to the intensity of leukocyte activation, inflammatory up-regulation and microcirculatory disruption associated to ischemia-reperfusion injury. Microvascular integrity and inhibition of pro-inflammatory mediators are key-factors in the evolution of AP. Relaxin is an insulin-like hormone that has been attributed vasorelaxant properties via the nitric oxide pathway while behaving as a glucocorticoid receptor agonist. METHODS: AP was induced by the bilio-pancreatic duct-outlet-exclusion closed-duodenal-loops model. Treatment with relaxin was done at different time-points. Nitric oxide synthase inhibition by L-NAME and glucocorticoid receptor (GR) blockage by mifepristone was considered. AP severity was assessed by biochemical and histopathological analyses. RESULTS: Treatment with relaxin reduced serum amylase, lipase, C-reactive protein, IL-6, IL-10, hsp72, LDH and 8-isoprostane as well as pancreatic and lung myeloperoxidase. Acinar and fat necrosis, hemorrhage and neutrophil infiltrate were also decreased. ATP depletion and ADP/ATP ratio were reduced while caspases 2-3-8 and 9 activities were increased. L-NAME and mifepristone decreased the efficiency of relaxin. CONCLUSION: Relaxin resulted beneficial in the treatment of AP combining the properties of a GR agonist while preserving the microcirculation and favoring apoptosis over necrosis.

Influence of nitric oxide-donating nonsteroidal anti-inflammatory drugs on the evolution of acute pancreatitis.

Microcirculatory disturbances and leukocyte activation are main events in the pathogenesis of acute pancreatitis (AP) that is characterized by inflammatory up-regulation. Nitric oxide-donating nonsteroidal anti-inflammatory drugs (NO-NSAIDs) regulate vascular function and mitigate inflammation. To investigate the influence of NO-NSAIDs on AP. AP was induced by the biliopancreatic duct outlet exclusion-closed duodenal loops model. Treatment with NO-flurbiprofen, NO-ibuprofen, NO-aspirin, or their parental drugs was done (i) 1 h before, (ii) 1 h after, (iii) 1 h before and 4 h after, or (iv) 4 h after surgery. The degree of severity was evaluated using biochemical and histopathological analyses. NO-NSAIDs given before and during the first hour of the noxia decreased blood levels of amylase, lipase, C-reactive protein, IL-6, IL-10, heat shock protein 72, prostaglandin E2 inactive metabolite, and 8-isoprostane, as well as pancreatic and lung myeloperoxidase and cyclooxygenase. Acinar and fat necrosis, hemorrhage, and leukocyte infiltrate were also reduced. The best protection was achieved when treatment was performed 1 h before and 4 h after triggering AP. NO-flurbiprofen was the most effective drug. AP severity was significantly ameliorated by NO-NSAIDs being the administration time essential to achieve optimal pancreatic protection that may result to be useful in the prevention of postendoscopic severe AP.

Influence of stress in acute pancreatitis and correlation with stress-induced gastric ulcer.

BACKGROUND AND AIMS: In the general adaptation syndrome, gastric lesions are the first manifestation of stress. We hypothesized that acute pancreatitis (AP), an inflammatory acute disease, will be exacerbated if unchained following stress. Visceral hypersensitivity will be enhanced due to catecholaminergic discharges leading to an over-induction of the intrapancreatic cholinergic tone with increased response of the pancreocyte to cholecystokinin (CCK). Our aim was to investigate the influence of stress before AP on the later AP, and the effect of AP on underlying diseases such as gastric ulceration. METHODS: The model of stress induced by restraint was followed by the bilio-pancreatic duct outlet exclusion closed duodenal loops model. The effect of autonomous arc reflex (AAR) interruption by anesthetics after stress but before AP was assessed. The participation of the vagal and sympathetic pathways and involvement of CCK-A receptors were considered. The degree of severity was evaluated using biochemical and histopathological analyses. RESULTS: Induction of AP after stress was more severe than in its absence. Acinar and fat necrosis, hemorrhage and neutrophil infiltrate foci were evenly distributed, being significantly greater in size and number after stress. Gastric ulceration evolved to ulcer, hemorrhage and gastric necrosis after AP triggering. Serum amylase, lipase, C-reactive protein, IL-6, IL-10 and plasmatic hsp72 as well as pancreatic and lung myeloperoxidase were significantly elevated in AP after stress while pancreatic amylase and lipase were significantly reduced. AAR blockage ameliorated AP after stress. CONCLUSIONS: Stress aggravates pancreatic pathology while AP deteriorates gastric pathology, and anesthetic treatment was beneficial for both. Restraint in other animal models can be useful to study the influence of stress in the evolution of other diseases.

Acute pancreatitis possible initial triggering mechanism and prophylaxis.

BACKGROUND AND AIMS: Biliary acute pancreatitis or postendoscopic iatrogenia acute pancreatitis (AP) are likely triggered by autonomous arc reflexes (AAR) initiated in the peri-Vaterian duodenum (PV-D). The bilio-pancreatic duct outlet exclusion closed duodenal loops (BPDOE-CDL) model mimics these circumstances. Our aim was to validate this model and evaluate the role of AAR via their interruption with local anesthetics. METHODS: Severe AP was induced in Wistar rats with the BPDOE-CDL model: extra-pancreatic insult was provoked in the PV-D by distension with 8% sodium taurocholate and methylene blue for 45 min to show the absence of duodenum pancreatic reflux. Treated experimental groups received a 2% lidocaine chlorhydrate gel instilled into the PV-D prior to triggering the AP, or before and after at the celiac-ganglia complex, or at both sites. The degree of severity was evaluated using biochemical and histopathological analysis. RESULTS: Induction of AP by BPDOE- CDL was severe, with acinar and fat necrosis and hemorrhage with a greater foci number in the cephalic segment. Groups pretreated with local anesthetic developed mild or moderate AP characterized by edema and leukocyte infiltrate. Serum amylase, lipase and CRP were significantly reduced in all treated groups. Other blood metabolites and pancreatic myeloperoxidase, amylase and lipase, were significantly decreased. CONCLUSION: The BPDOE-CDL model was validated, emphasizing the importance of AAR as extrapancreatic initiators of AP. The interruption of AAR by lidocaine chlorhydrate prevented excessive pancreatic inflammation and diminished hemorrhage and necrosis and may prove a useful prophylactic procedure to prevent postendoscopic severe AP.

Experimental model of acute pancreatitis in Wistar rat: glucocorticoid treatment profile.

Severe acute pancreatitis may be triggered by an extrapancreatic insult at the peri-Vaterian duodenum such as that occurring in the short-term, 20 min closed duodenal loop model in Wistar rat, which mimics biliary acute pancreatitis or that following endoscopy. Glucocorticoids are immunological modulators whose therapeutic value is worth investigating. Wistar male rats were used under standardized conditions. Acute pancreatitis was induced by instillation of a 7% sodium tauraocholate solution with 5 drops of methylene blue to monitor absence of duodenal bilio pancreatic reflux into the peri-Vaterian duodenum for 20 min. Detection of biliopancreatic reflux with methylene blue was an exclusion criterion. Different doses and times of administration of subcutaneous hydrocortisone were evaluated. Biochemical assays were carried out in blood samples and pancreatic and lung tissue, while histpathological studies were done in the pancreas, lung liver, duodenum, spleen, kidneys, suprarenal glands, and stomach. Animals subjected to the experimental model developed severe acute pancreatitis. According to the dose and time of administration, hydrocortisone therapy was effective and beneficial at a dose of 4 mg/kg give 30 min before inducing acute pancreatitis. It was ineffective when doses were <4 mg/kg and given before sodium taurocholate harmful when the dose was >4 mg/kg and given either before or after. Thus, the proposed model is valid and useful to study the initiation mechanism of acute pancreatitis caused extrapancreatically while its amelioration by glucocorticoid is related the dose and time factor to achieve therapeutical results.

Colonic proteinase: increased activity in patients in patients with ulcerative colitis

In order to study the colonic intraluminal proteinase-antiproteinase imbalance under inflammatory conditions, we determined proteolytic activity (PA), alpha-1-antitrypsin and the activities of trypsin, chymotrypsin and neutrophil elastase in feces from patients with ulcerative colitis (UC) comparing the results with a control group. A fecal sample was obtained from each of 25 patients with ulcerative colitis and 10 control subjects were studied. The severity of the disease was assessed by the Truelove index. Proteolytic activity was measured lesing azocasein as proteolytic substrate. The fecal concentration of alpha-1-antitrypsin was measured by radial immunodiffusion and the activities of the enzymes were measured using specific substrates. We found an increase in fecal PA, alpha-1-antitrypsin and neutrophil elastase in patients with UC and the correlation between the severity of the disease and the PA was statistically significant (r = 0.62, P < 0.05). We conclude that elevated colonic proteinase activity could contribute to the pathophysiology of ulcerative colitis.

Caracterización de formas macroenzimáticas de la fosfatasa alcalina: descripción de un nuevo método / A new method for the characterization of alkaline phosphatase macroenzymes

Se describe un nuevo método para la caracterización de macroenzimas de la fosfatasa alcalina. El método combina una separación previa de las formas isoenzimáticas por gel filtración en capa fina de Sephadex G-200, y el posterior revelado de la correspondiente actividad enzimática in situ. Entre otras ventajas, este sistema no sólo separa adecuadamente las formas macroenzimáticas, sino que mantiene todas las isoenzimas en estado nativo, a diferencia de las técnicas con desnaturalizantes, por lo que es posible su detección y eventual aislamiento. Permite además la resolución simultánea de un gran número de muestras, así como la inclusión de controles de distinto peso molecular (PM) dentro de una misma corrida, lo que facilita en forma significativa la posterior interpretación del perfil obtenido, aportando una gran ventaja con respecto a la técnica de gel filtración en columna. El método propuesto se presenta como una técnica relativamente simple y rápida para el screening de macroenzimas en el laboratorio clínico