Differential involvement of the opioid receptor antagonist naloxone in motivational and hedonic aspects of reward.

摘要: In the present study dose-dependent effects of opioid receptor antagonist naloxone were investigated on rewarding sweetened condensed milk (SCM) in four behavioral paradigms addressing hedonic, consummatory as well motivational aspects a reward: odour-conditioned pleasure attenuation acoustic startle response (PAS), conditioned place preference (CPP), voluntary consumption limited access paradigm, break point determination progressive ratio (PR) task. A reduction reward-related behavior was observed all paradigms, with exception PR task, which not affected by at all. CPP for SCM only highest dose naloxone. The results indicate that is more effective suppressing hedonic than reward, further supporting involvement endogenous system mediation properties food reward.