Antinociceptive and pharmacological effects of metanicotine, a selective nicotinic agonist.

Abstract

Metanicotine [N-methyl-4-(3-pyridinyl)-3-butene-1-amine], a novel neuronal nicotinic agonist, was found to bind with high affinity (K(i) = 24 nM) to rat brain [(3)H]nicotine binding sites and it generalized to nicotine in a dose-dependent manner in the drug discrimination procedure. Metanicotine produced significant antinociceptive effects in mice and rats subjected to either acute thermal (tail-flick), mechanical (paw-pressure), chemical (para-phenylquinone), persistent (Formalin), and chronic (arthritis) pain stimuli. Metanicotine was about 5-fold less potent than nicotine in the tail-flick test after s.c administration, but slightly more potent after central administration. Its duration of action was longer than that of nicotine. Nicotinic antagonists, mecamylamine and dihydro-beta-erythroidine, blocked metanicotine-induced antinociception in the different pain models. However, the antinociceptive effect was not affected by pretreatment with either naloxone or by atropine, confirming that metanicotine exerts its antinociceptive effect via nicotinic rather than either opioid or muscarinic mechanisms. In contrast to nicotine, antinociceptive effects of metanicotine were observed at doses that had virtually no effect on spontaneous activity and body temperature in mice. These data indicate that metanicotine is a centrally acting neuronal nicotinic agonist with preferential antinociceptive effects in animals. Thus, metanicotine and related nicotinic agonists may have great potential for development as a new class of analgesics.

• Authors: M I Damaj, W Glassco, M D Aceto, B R Martin
• Journal: The Journal of pharmacology and experimental therapeutics (J Pharmacol Exp Ther) Vol. 291 Issue 1 Pg. 390-8 (Oct 1999) ISSN: 0022-3565 [Print] United States
• PMID: 10490929 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Analgesics
• Nicotinic Agonists
• Receptors, Cholinergic
• metanicotine
• Nicotine

Topics

• Analgesics (pharmacology)
• Animals
• Binding, Competitive
• Body Temperature (drug effects)
• Discrimination Learning
• Male
• Mice
• Mice, Inbred ICR
• Motor Activity (drug effects)
• Nicotine (analogs & derivatives, pharmacology)
• Nicotinic Agonists (pharmacology)
• Pain Measurement
• Rats
• Rats, Sprague-Dawley
• Receptors, Cholinergic (metabolism)