Antagonistic effect of buprenorphine on the antitussive effect of morphine is mediated via the activation of mu 1-opioid receptors.
The effect of buprenorphine on the antitussive effect of morphine was examined in mice. Buprenorphine at doses of 0.1, 0.3 and 1 mg/kg given i.p. alone have no effects on the % inhibition in the number of capsaicin-induced coughs. However, pretreatment with the same doses of buprenorphine for 2 hr significantly attenuated the antitussive effect of morphine (3 mg/kg, i.p.). Naloxonazine, a selective mu 1-opioid receptor antagonist, had no effect of buprenorphine on antitussive effect of morphine. These results suggest that buprenorphine antagonizes the antitussive effect of morphine via the activation of mu 1-opioid receptors.
Kamei
J
J
Department of Pathophysiology & Therapeutics, Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo, Japan.
Saitoh
A
A
Morita
K
K
Nagase
H
H
D000818:Animals; D000996:Antitussive Agents / Q000494:pharmacology*; D002047:Buprenorphine / Q000494:pharmacology*; D002211:Capsaicin; D003371:Cough / Q000139:chemically induced; D007274:Injections, Intraperitoneal; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009020:Morphine / Q000494:pharmacology*; D009270:Naloxone / Q000031:analogs & derivatives / Q000494:pharmacology; D017450:Receptors, Opioid, mu / Q000187:drug effects*; D013997:Time Factors
D000996:Antitussive Agents; D017450:Receptors, Opioid, mu; D009270:Naloxone; D002047:Buprenorphine; D009020:Morphine; C034643:naloxonazine; D002211:Capsaicin