Endogenous kappa-opioid systems in opiate withdrawal: role in aversion and accompanying changes in mesolimbic XXXX release.

@entity3347 @entity935 @entity14719 @entity1510 @entity1286 @entity35 @entity734
The kappa-opioid receptor antagonist @entity14719 ( @entity14719 ) was recently shown to potentiate certain overt withdrawal signs in @entity1286 -dependent @entity35 . The present study sought to further assess this phenomenon by examining the influence of @entity14719 treatment upon the conditioned place aversion associated with the @entity1510 -precipitated @entity3347 . In addition, in vivo microdialysis studies were conducted in @entity1286 -dependent @entity35 to determine whether @entity14719 treatment can modify withdrawal-induced changes in basal @entity935 (DA) release within the mesolimbic system. @entity35 were pretreated with either saline or a single dose of @entity14719 and then received ascending doses of @entity1286 for 10 days. A @entity3347 was then precipitated by the administration of @entity1510 (1 mg/kg SC). In @entity35 which received chronic @entity1286 injections, administration of @entity1510 produced a characteristic @entity3347 and a marked aversion for an environment previously associated with @entity1510 -precipitated withdrawal. @entity14719 treatment potentiated most overt signs of @entity734 . This treatment also resulted in a greater withdrawal-induced place aversion. @entity1286 -dependent @entity35 exhibited a marked reduction in basal mesolimbic DA release. An even greater decrease in basal DA release was observed in @entity14719 treated @entity35 . These results suggest that endogenous kappa-systems are important in the modulation of mesolimbic DA release and the accompanying place aversion which occurs during opiate withdrawal.
