Calcium agonists and antagonists of the dihydropyridine type: effect on nicotine-induced antinociception and hypomotility.
The influence of a calcium agonist (BAYK 8644) and several calcium channel blockers on nicotine-induced antinociception was investigated in mice. The effect of nicotine was sharply increased by BAYK 8644. This potentiation by BAYK 8644 was blocked by pretreating the animals with nifedipine at 2 and 10 mg/kg. The calcium channel antagonists, nifedipine and nimodipine at doses that had no effect on tail-flick time, reduced significantly the antinociception induced by nicotine (1.5 mg/kg, s.c.). However, the effect of verapamil on nicotine was not significant. These results indicate that DHP calcium channels (type L-channel) play a role in some of the pharmacological effects of nicotine, particularly, locomotor activity and antinociception.
Damaj
M I
MI
Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0613.
Martin
B R
BR
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology*; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects*; D009538:Nicotine / Q000494:pharmacology*; D009619:Nociceptors / Q000187:drug effects*; D017288:Pain Threshold / Q000187:drug effects; D011950:Receptors, Cholinergic / Q000187:drug effects*
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D011950:Receptors, Cholinergic; D009538:Nicotine; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester