The effects of KB-2796 and BAY K 8644 on fentanyl-induced analgesia in rats.
We investigate the modulatory effects of subcutaneous administration of different doses of KB-2796 (1, 5 and 15 mg/kg), a new calcium channel blocker, and BAY K 8644 (0.25, 0.5 and 1 mg/kg), a calcium agonist, on fentanyl-induced analgesia (20 micrograms/kg) in rats. The drugs were tested individually as well as in combination with fentanyl. Dimethyl sulfoxide (DMSO) was used as a control. Nociceptive sensitivity was assessed by the tail-flick technique. When KB-2796 and BAY K 8644 were used alone, only KB-2796 at the dose of 15 mg/kg produced an effect that was significantly different from that of DMSO (p < 0.01). The effect was antinociceptive. When administered with fentanyl, KB-2796 at 5 and 15 mg/kg potentiated the analgesic effect of fentanyl (p < 0.05), but suppression of fentanyl analgesia by BAY K 8644 was not significant at any of the doses tested. Our data supports the hypothesis that the calcium ion is partially involved in fentanyl-induced analgesia.
Wong
J O
JO
Department of Anesthesiology, National Cheng Kung University Medical College, Tainan, Taiwan, R.O.C.
Chang
C L
CL
Cheng
J T
JT
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology*; D000698:Analgesia; D000818:Animals; D002118:Calcium / Q000502:physiology; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004347:Drug Interactions; D005283:Fentanyl / Q000494:pharmacology*; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D002121:Calcium Channel Blockers; D010879:Piperazines; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; C052424:lomerizine; D002118:Calcium; D005283:Fentanyl