title: Circadian variations in the renal toxicity of gentamicin in rats.
abstract: The hypothesis that sublethal doses of aminoglycosides cause renal tubule disorders resulting in changes of urine enzyme levels was investigated. The renal status following injection of a single sublethal dose of gentamicin (200 mg/kg) at different times during a 24 h cycle was studied. Increased excretion of gamma-glutamyl transferase, alanine aminopeptidase and N-acetyl-beta-D-glucosaminidase, used clinically as markers for tubule toxicity of aminoglycosides, was maximal when gentamicin was administered to rats at 2 p.m. and was minimal when injected at 8 p.m. These significant differences in enzyme excretion as a function of injection time are correlated with the concentration of gentamicin in the urine and in the renal cortex.
mesh_terms: D000118:Acetylglucosaminidase / Q000652:urine; D000626:Aminopeptidases / Q000652:urine; D000818:Animals; D018826:CD13 Antigens; D002940:Circadian Rhythm; D004305:Dose-Response Relationship, Drug; D005839:Gentamicins / Q000633:toxicity*; D007668:Kidney / Q000187:drug effects*; D007672:Kidney Cortex / Q000187:drug effects; D007684:Kidney Tubules / Q000187:drug effects; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D005723:gamma-Glutamyltransferase / Q000652:urine
chemical_list: D005839:Gentamicins; D005723:gamma-Glutamyltransferase; D000118:Acetylglucosaminidase; D000626:Aminopeptidases; D018826:CD13 Antigens