Non-opioid psychotomimetic-like discriminative stimulus properties of N-allylnormetazocine (SKF 10,047) in the rat.

The purpose of this study was to characterize the discriminative stimulus property of dl-SKF 10,047 in the rat and to investigate if this property is the result of an interaction with opiate receptors or dopaminergic mechanisms. Male Sprague Dawley rats were trained in a two-lever food-reinforced procedure to discriminate between the effect of saline and of dl-SKF 10,047 (5 mg/kg). The trained rats dose dependently generalized the effect of dl-, d- and l-SKF 10,047, as well as cyclazocine, phencyclidine and ketamine but did not generalize the effect of either fentanyl, morphine, bremazocine, ethylketocyclazocine, pentazocine, nalorphine, naloxone, MR 2266, d-lysergic acid diethylamide, apomorphine or d-amphetamine. Neither naloxone, MR 2266, fentanyl, ethylketocyclazocine nor haloperidol antagonized the discriminative stimulus produced by dl-SKF 10,047. These data suggest that the discriminative stimulus property of dl-SKF 10,047 in the rat is not due to its interaction with either opiate receptors or dopaminergic mechanisms but may be related to its psychotomimetic effect in man.