The effects of tiadenol, clofibrate and clofibride on bile composition in the rat.

Biliary secretion was studied in normolipidemic rats after a 7 day treatment with the hypolipidemic drugs, tiadenol (bis-(hydroxyethylthio)-1,10-decane), clofibrate and clofibride (chloro-4-phenoxy-2-methyl-2-propionate of dimethylcarbamoyl-3-propyl). All three drugs decreased blood cholesterol and total lipids, increased liver weight and liver catalase content, and decreased biliary excretion of cholesterol. The biliary concentrations of bile salts, phospholipids and cholesterol decreased to a variable extent, in such a way that the ratio of bile salts + phospholipids to cholesterol was increased by the drugs. The bile salt independent fraction was increased. The effects were qualitatively similar for all three drugs tested, but quanitative differences appeared for some of the parameters.

Effects of different cellulose derivatives on drug release mechanism studied at a preformulation stage.

As a matter of fact, in vitro dissolution is well known to be the method of choice for the pharmaceutical industry to develop effective medicines. However, many experiments must be performed all along a new product life and they represent an overcharge of work for researchers. The purpose of this paper was to assess the relevance of new parameters obtained during preformulation stage by Nuclear Magnetic Resonance (NMR) experiments to better understand drug release mechanism. This study was carried out with three cellulose derivatives currently used as carrier matrices (Microcrystalline cellulose (MCC), Hydroxypropylmethyl cellulose (HPMC) and Ethyl cellulose (EC)). Granules and tablets were produced with these three excipients (60% w/w) and theophylline as drug model (40%). On the one hand, in vitro dissolution studies were performed with the rotating paddle method displaying the different release behaviour of these three matrices (immediate release for MCC, steady release for HPMC and sustained release for EC). On the other hand, the evolution of the T2m spin-spin relaxation time in NMR experiments during granules hydration was recorded. NMR findings shore up dissolution data, both depending on interactions between the matrix and water. NMR spectroscopy appears to be a valuable tool for obtaining, at an earlier stage of drug development, more information about drug release mechanism.

Contributions of AMPA and GABA(A) receptors to the induction of NMDAR-dependent LTP in CA1.

The contributions of (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and gamma-aminobutyric acid (GABA[A]) receptors in the induction of long-term potentiation (LTP) have been studied in the CA1 region of the rat hippocampus. The results suggest that: (1) in physiological conditions, AMPARs are necessary for the induction of N-methyl-D-aspartate receptor (NMDAR)-dependent LTP since LTP cannot be elicited in the presence of the AMPAR antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Although a NMDAR-dependent LTP occurs in the presence of a GABA(A) antagonist and high concentrations of divalents cations, blockade of AMPARs leads to a voltage-dependent calcium channels (VDCC)-dependent LTP since its induction is blocked by nifedipine and not by APV. (2) The bicarbonate-induced GABA(A) receptor-mediated depolarizing response is not necessary in the induction of NMDAR-dependent or VDCC-dependent LTP since induction of these two types of LTP were not blocked by acetazolamide or in a nominally bicarbonate-free solution.

[Primary exocrine pancreatic insufficiency in the adult. Presentation of a case]. / Insuffisance pancréatique exocrine primitive de l'adulte. Présentation d'un cas.

The authors report the case of a 37-year-old female complaining of chronic diarrhea since childhood. She had gross steatorrhea and azotorrhea . Pancreatic function tests using secretin and cholecystokinin-pancreozymin stimulation, and analysis of pure pancreatic juice collected under secretin stimulation proved exocrine pancreatic insufficiency. Oral glucose tolerance test was normal. Intestinal absorption tests, small bowel X-ray films and jejunal histology were normal. Brush-border specific enzyme activities were increased. In vitro palmitic acid uptake and esterification in the jejunal mucosa were decreased. There was no pancreatic calcification. Biliary tract was normal. Retrograde pancreatography, pancreatic ultrasonography and tomodensitometry showed no morphologic abnormality. No cause of exocrine pancreatic insufficiency could be detected. A son and a niece of the proband had chronic diarrhea and growth failure. The relationship of the described case with primary lipomatosis of the pancreas in childhood and hereditary exocrine pancreatic insufficiency in CBA/J epi mice is discussed.

[A case of hepatocholangitis (author's transl)]. / Une observation d'hépaticite (hépato-cholangite).

Inflammation localised to the hepatic duct in the region of the neck of the gallbladder is rare. Regression of the lesions after cholecystectomy authentified its purely inflammatory nature. Its interest comes from possible confusion with carcinoma of the common bile duct. A case of cholangitis with 8 years follow up illustrates these facts and permits a few comments on the pathology of the junction between the cystic duct and the hepatic duct.