PubMed Health⌕ Search

Biomedical subjects

M Beraud

Publications and source records attributed to M Beraud.

24 records · Page 2Linked to original sources
PubMed1980

Phagocytic activity of the rat reticuloendothelial system and the pharmacokinetics of an anticholinesterasic insecticide: carbaryl.

1. The pharmacokinetics of [14C]carbaryl administered intravenously and orally were studied in male rats whose reticuloendothelial system (RES) was inhibited by colloidal carbon or activated by glyceryl trioleate. 2. A time course for [14C]carbaryl blood concn. was fitted to a two-compartment open model following single intravenous administration. A single exponential decay was noted following intragastric administration. 3. The constant blood elimination of [14C]carbaryl decreased significantly in animals with the RES inhibited and increased in those whose RES was activated compared to control animals. 4. There was an increase in carbaryl concn. in the tissue compartment in animals with the RES activated, but no change in animals with the RES inhibited. 5. The equivalent [14C]carbaryl concn. of liver and lungs were decreased or increased in animals with the RES inhibited or activated respectively.

Animals↗
PubMed1978

[Relationship between the phagocytic inhibition of the rat reticuloendothelial system and the anticholinesterasic effect of an insecticide, Carbaryl (author's transl)].

Phagocytic activity of the reticuloendothelial system (RES) and blood cholinesterase activity were determined in male rats after veinous administrations of carbaryl and 1-naphthol, a carbaryl metabolite. The various parameters were measured 1, 24, 48 and 72 hours after administration of the following four doses per 100 g body weight : 1.875, 3.75, 7.5 and 15 mumol. 1. Results showed an inhibition of the RES phagocytic activity (clearance of colloidal carbon) after carbaryl administration; although 1.875 mumol/100 g had no effect, the other doses inhibited RES activity, blockade time being a function of the dose given. The phagocytic function had returned to normal 72 hr after carbaryl administration. 2. Reductions in spleen weight and protein content were observed together with the RES blockade. 3. At all four doses, the anticholinesterase effect was already apparent one hour after carbaryl administration. 4. 1-naphthol, one of carbaryl's chief metabolites, had no effect either on the RES or on the different parameters studied. These results show a relationship between the phagocytic inhibition of the reticuloendothelial system and the anticholinesterasic effect by carbaryl. They suggest an inhibition of some esterases of macrophages interfering with the phagocytosis.

Animals↗
PubMed1975

[Effect of ingestion of derivatives of quinoxaline on the enzymatic detoxication activity of hepatic microsomes in the rat].

Female rats received quinoxaline, 2,3-dimethyl quinoxaline, 2,3-diphenyl quinoxaline and 2,3-dithiol quinoxaline by oral intubation for 4 days (500 mg/kg/day) and drug-metabolizing enzymes were investigated. A significant stimulation in liver microsomal enzymes occurred after 2,3-dimethyl quinoxaline and 2,3-diphenyl quinoxaline treatments; these changes were associated with increases in cytochrome P-450 level and in RNA and protein contents of the microsomal fraction. Quinoxaline had no effect on the metabolic rate of the studied substrates but increased the cytochrome P-450 and the RNA and protein levels; whereas, 2,3-dithiol quinoxaline inhibited the aminopyrine and N-methylaniline N-demethylations and decreased the cytochrome P-450 per mg microsomal protein.

Animals↗