title: Absorption and metabolism in man of 16-epi-gitoxin, a new semi-synthetic cardioactive glycoside.
abstract: The pharmacokinetics of 3H-16-epi-gitoxin have been investigated after oral administration: The peak serum level occurred after 30-60 min, and its subsequent decline was in two phases with half-lives of 3.5 and 19.5 h, respectively. Within 3 days 66-70% of the administered radioactivity were eliminated by renal excretion. In the first 16 h 15% of excreted activity was in metabolites, but thereafter the glycoside was excreted in unchanged form. The metabolites were characterized by thin-layer chromatography and radio-scanning; it is assumed that they correspond to the bis- and monodigitoxosides as well as to the genin of 16-epi-gitoxin. The unusual pharmacokinetics of the glycoside are discussed in relation to its special kinetics at the molecular level, i.e. the rapid dissociation rate of the glycoside-(Na+ + K+)-ATPase-complex.
mesh_terms: D000328:Adult; D002855:Chromatography, Thin Layer; D004071:Digitalis Glycosides / Q000097:blood / Q000378:metabolism* / Q000652:urine; D005260:Female; D006207:Half-Life; D006801:Humans; D007408:Intestinal Absorption; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D004071:Digitalis Glycosides