The metabolism of nicotine-Δ1′(5′)-iminium ion,in vivo andin vitro

Abstract
Nicotine-Δ1′(5′)-iminium ion, either as the diperchlorate or the hydrochloride, is rapidly converted into cotinine by a hepatic cytoplasmic enzyme. Incubations in an atmosphere of nitrogen indicated that the oxygen incorporated into cotinine is derived from water. Following the intraperitoneal administration of nicotine-Δ1′(5′)-iminium ion to guinea pigs or rats, cotinine, and nicotine1′-N-oxide were found in the urine. The results support the idea that nicotine-Δ1′(5′)-iminium ion is an intermediate in the metabolic conversion of nicotine to cotinine.