title: Metabolism of paraldehyde to acetaldehyde by rat liver microsomes.
abstract: Paraldehyde (PAL) was shown to be metabolized to acetaldehyde (AcH) by rat liver microsomes in vitro only when the cofactors for the cytochrome P-450 system were present. Microsomes from phenobarbital treated rats significantly increased the amount of AcH produced from PAL. Attempts to inhibit this reaction by addition of SKF-525A to the incubation medium resulted in augmentation of the AcH generated, very likely due to the metabolic deethylation of SKF-525A itself to AcH. Rats pretreated with D-penicillamine and then given PAL excreted 2,5,5-trimethylthiazolidine-4-carboxylic acid (TTCA)-a condensation product of AcH and D-penicillamine-in the urine. These results strongly suggest that PAL is metabolized in vivo by the hepatic microsomal system giving rise to AcH as a metabolite.
mesh_terms: D000079:Acetaldehyde / Q000378:metabolism*; D000818:Animals; D001711:Biotransformation; D002855:Chromatography, Thin Layer; D007700:Kinetics; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D010242:Paraldehyde / Q000378:metabolism*; D010396:Penicillamine / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology; D011335:Proadifen / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D011335:Proadifen; D010396:Penicillamine; D000079:Acetaldehyde; D010242:Paraldehyde; D010634:Phenobarbital