Isolation and microsequencing of a novel cotinine receptor.

1. Nicotine and its main derivative. cotinine, are reported to have distinct central activities in mammals.

Evidence that nicotine acetylcholine receptors are not the main targets of cotinine toxicity.

The toxicity of nicotine, cotinine and their mixtures was studied in Mus musculus mice as well their effects on growth after repetitive administration to young mice. The affinity constants of the two alkaloids for the nicotinic acetylcholine receptors (nAChRs) of Torpedo and rat brain membranes were determined. The administration of these alkaloids produced distinct symptoms of intoxication.

Nicotine is more efficient than cotinine at passing the blood-brain barrier in rats.

1. Nicotine and its main metabolite, cotinine, were reported to have distinct behavioral activities in mammals. 2.