Modulation of nicotine-induced analgesia by calcium agonist and antagonist in adult rats.
The involvement of calcium in nicotine-induced analgesia in male rats was explored using the tail-flick test. A single dose of nicotine (1 mg/kg SC) produced a maximal effect on tail-flick latency (15 s) within 8-10 min, which lasted for 4 min. Pretreatment with the calcium chelator, EDTA (250 microM/kg SC four injections at 15 min intervals), before the single dose of nicotine accelerated the onset and prolonged the duration of the nicotine-induced analgesia. The maximal effect on tail-flick latency occurred within 2 min and lasted for 10-20 min. Conversely, pretreatment with calcium chloride (1.5 mM/kg IP) attenuated nicotine-induced analgesia. It is suggested that nicotine may exert its antinociceptive effects via modulation of calcium fluxes across the neural membrane.
Chin
C W
CW
Department of Anesthesiology, UMD-NJ Medical School, Newark 07103-2714.
Block
R C
RC
Wu
W H
WH
Zbuzek
V K
VK
D000698:Analgesia; D000818:Animals; D002120:Calcium Channel Agonists / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002122:Calcium Chloride / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004492:Edetic Acid / Q000494:pharmacology; D008297:Male; D009538:Nicotine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D010147:Pain Measurement / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D002120:Calcium Channel Agonists; D002121:Calcium Channel Blockers; D009538:Nicotine; D004492:Edetic Acid; D002122:Calcium Chloride