Mecamylamine reduces nicotine cross-desensitization of trigeminal caudalis neuronal responses to oral chemical irritation.
We investigated the role of neuronal nicotinic acetylcholine receptors (nAChRs) in nicotine cross-desensitization of chemonociceptive responses of trigeminal subnucleus caudalis (Vc) neurons in rats. Vc responses to lingually applied pentanoic acid were significantly reduced following nicotine, and this was prevented when the nAChR antagonist mecamylamine was applied before or after nicotine. A peripheral site of nicotine cross-desensitization is suggested via a nAChR-mediated reduction in acidic excitation of lingual nociceptors that project to Vc.
Section of Neurobiology, Physiology and Behavior, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA.
Christopher T
CT
Simons
Satoko
S
Sudo
Makoto
M
Sudo
E
E
Carstens
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D004361:Drug Tolerance / Q000502:physiology; D008297:Male; D008464:Mecamylamine / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D009538:Nicotine / Q000494:pharmacology; D018722:Nicotinic Agonists / Q000494:pharmacology; D018733:Nicotinic Antagonists / Q000494:pharmacology*; D009619:Nociceptors / Q000502:physiology; D010421:Pentanoic Acids / Q000494:pharmacology; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000502:physiology*; D014059:Tongue / Q000187:drug effects / Q000294:innervation; D014275:Trigeminal Caudal Nucleus / Q000187:drug effects* / Q000502:physiology
D018722:Nicotinic Agonists; D018733:Nicotinic Antagonists; D010421:Pentanoic Acids; D011978:Receptors, Nicotinic; D008464:Mecamylamine; D009538:Nicotine