[The effects of cholestyramine on pancreatic secretion]. / Efectos de la colestiramina sobre la secreción pancreática.

The objective was to evaluate the effect of biliary salt depletion on morphology and function of the exocrine pancreas. Cholestyramine (15 g/day) was given during fifteen days to male Wistar rats in order to evaluate changes in pancreas weight as well as in enzymatic content of pancreatic tissue and duodenal juice (amylase, lipase and trypsinogen); in duodenal juice, bile salt concentration was also measured; Moreover ultrastructure of the exocrine pancreas was studied. Our results show an increase in pancreas weight in rats treated with cholestyramine, with a significant increase of amylase (p < 0.05) and trypsinogen in pancreatic tissue (p < 0.01), and of lipase in duodenal juice (p < 0.05). Ultrastructural changes were absent. It is concluded that cholestyramine, probably through a bile salt depletion, stimulates pancreatic function and growth, as well as lipase secretion.

[Modifications of the enzymatic content and morphology of the exocrine pancreas of rats with experimental hepatic cirrhosis induced by thioacetamide]. / Modificaciones del contenido enzimático y de la morfología del páncreas exocrino de rata con cirrosis hepática experimental inducida por tioacetamida.

In order to assess the experimental level of enzymatic content in exocrine pancreas of cirrhotic rats, cirrhosis was induced with administration of thioacetamide (50 mg/kg) during ten weeks to male Wistar rats with an initial average weight of 350 g. Contents of amylase, lipase and trypsinogen were determined in pancreatic tissues and amylase, lipase and biliary salts in duodenal juice obtained by cannulation and perfusion with physiologic serum. A higher presence of trypsinogen and amylase was detected in pancreatic tissues, and of lipase in the duodenal juice, with a trend, although insignificant, towards a decrease in biliary salts among the cirrhotic group. No changes were observed in the morphologic study. The hypothesis that a deficit of biliary salts in experimental cirrhosis could be responsible of the enzymatic increase in the pancreatic tissue and, in particular, of the selective excretion of lipase, is discussed.

[Use of a rapid method for detecting adenovirus in the feces of children]. / Utilidad de una técnica rápida para detección de adenovirus en heces de niños.

Adenovirus (ADV) and rotavirus (RV) were screened by latex aglutination (LA) in 772 fecal samples from hospitalized and non hospitalized children under 7 years of age, those included 55 control samples. Reactive samples were confirmed by electron microscopy (ME) and enzimoimmunoassay (EIA). ADV were found in 20 (2.6%) samples and RV in 25 (3.2%). Coinfection by both viruses was not demonstrated. The greatest percentage of findings was observed in watery (23% ADV and 25% RV) and almost watery stools (8% ADV and 25% RV). We did not find any of those viruses in samples from control children. Concordance between LA and confirmation methods used was excellent. Thus the LA tests could provide a simple tool for the diagnosis of non hospitalized patients, increasing the possibilities of a rapid ethiological diagnostic in infectious diarrhoeas.

Ultrastructure of the proximal convoluted tubule in the hibernating garden dormouse (Eliomys quercinus L.).

We have carried out an ultrastructural study of the proximal convoluted kidney tubule in hibernating and nonhibernating garden dormice. Deep hibernation produced the following changes: the nuclei had an irregular shape; saccular cavities appeared near the nucleus and there was an increase in the components of the lysosomal system; hibernation seems to have no influence on the number of mitochondria; hypertrophic mitochondria occur in controls, whereas none were ever seen in hibernating dormice.

[Ultrastructural changes in the renal filtration barrier during hibernation of the common dormouse (Eliomys quercinus L.)]. / Changements ultrastructuraux de la barrière de filtration rénale au cours de l'hibernation chez le lérot commun (Eliomys quercinus L.).

We have studied kidney samples of 16 garden dormouses (Eliomys quercinus L.) divided into two groups, 8 hibernating and 8 non-hibernating. Hibernation produces structural modifications in the glomerular ultrafilter: (1) the endothelial pores decrease in number and size; (2) the podocytic food processes increase in number and the slit pores decrease in size; (3) in the basement membrane there are no structural morphological modifications. In short, we could say that the permeability of the glomerular ultrafilter decreases during hibernation. This fact helps to understand the decrease in the rate of urine formation that takes place in the presence of a low body temperature and a metabolic depression.