Antinociceptive studies of the optical isomers of N-allylnormetazocine (SKF 10,047).
In the mouse tail-flick test, neither the racemate of N-allylnormetazocine (NANM) nor its optical isomers showed antinociceptive activity. However, all three antagonized morphine's tail-flick effects. In the phenylquinone test in mice, the racemate and (-)-isomer of NANM showed agonist activity and antagonized morphine-induced antinociception. The (+)-isomer was inactive. The opioid antagonist, naloxone was effective versus morphine alone in the tail-flick and versus morphine, and (+/-)- and (-)-NANM in the phenylquinone test. Yohimbine, the alpha 2-receptor blocker, antagonized morphine in the tail-flick test. In the phenylquinone test, yohimbine was effective versus (+/-)- and (-)-NANM, but showed no activity versus morphine. The results suggest that morphine and NANM are acting at different sites. In addition, different alpha 2-adrenoceptors appear to be involved. Some implications regarding the analgesic and psychotomimetic properties of NANM are discussed.
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009020:Morphine / Q000494:pharmacology; D009270:Naloxone / Q000494:pharmacology; D010620:Phenazocine / Q000031:analogs & derivatives* / Q000494:pharmacology; D011942:Receptors, Adrenergic, alpha / Q000502:physiology; D011957:Receptors, Opioid / Q000502:physiology; D013237:Stereoisomerism; D015016:Yohimbine / Q000494:pharmacology
D000700:Analgesics; D011942:Receptors, Adrenergic, alpha; D011957:Receptors, Opioid; D015016:Yohimbine; D009270:Naloxone; C012134:SK&F 10047; D009020:Morphine; D010620:Phenazocine