title: The metabolic disposition of (S)-2-(3-tert-butylamino-2-hydroxypropoxy)-3-cyanopyridine in rats, dogs, and humans.
abstract: Studies of the metabolic disposition of (S)-2-(3-tert-butylamino-2-hydroxypropoxy)-3-[14C]cyanopyridine (I) have been performed in humans, dogs, and spontaneously hypertensive rats. After an iv injection of I (5 mg/kg), a substantial fraction of the radioactivity was excreted in the feces of rats (32%) and dogs (31%). After oral administration of I (5 mg/kg) the urinary recoveries of radioactivity for rat and dog were 19% and 53%, respectively, and represented a minimum value for absorption because of biliary excretion of radioactivity. In man, bililary excretion of I appeared to be of minor significance because four male subjects, after receiving 6 mg of I p.o., excreted 76% and 9% of the dose of radioactivity in the urine and feces, respectively. Unchanged I represented 58% of the radioactivity excreted in human urine. The half-life for renal elimination of I was determined to be 4.0 +/- 0.9 /hr. In contrast, unchanged I represented 7% and 1% of excreted radioactivity in rat and dog urine, respectively. A metabolite of I common to man, dog, and rat was identified as 5-hydroxy-I, which represented approximately 5% of the excreted radioactivity in all species. Minor metabolites of I in which the pyridine nucleus had undergone additional hydroxylation were present in dog urine along with an oxyacetic acid metabolite, also bearing a hydroxylated pyridine nucleus.
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000378:metabolism*; D001646:Bile / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D002855:Chromatography, Thin Layer; D004285:Dogs; D005243:Feces / Q000032:analysis; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D011725:Pyridines / Q000032:analysis / Q000378:metabolism* / Q000652:urine; D051381:Rats; D014018:Tissue Distribution
chemical_list: D000959:Antihypertensive Agents; D011725:Pyridines; C021276:MK 761