Kappa-opioid agonists directly inhibit midbrain dopaminergic neurons.

ABSTRACT: Dopaminergic neurons of the ventral tegmental area (VTA) play a critical role in motivation and reinforcement of goal-directed behaviors. Furthermore, excitation of these neurons has been implicated in the addictive process initiated by drugs such as morphine that act at the micro-opioid receptor (MOR). In contrast, kappa-opioid receptor (KOR) activation in the VTA produces behavioral actions opposite to those elicited by MOR activation. The mechanism underlying this functional opposition, however, is poorly understood. VTA neurons have been categorized previously as principal, secondary, or tertiary on the basis of electrophysiological and pharmacological characteristics. In the present study using whole-cell patch-clamp recordings, we demonstrate that a selective KOR agonist (U69593, 1 m

SUBMITTER: Margolis EB 

PROVIDER: S-EPMC6740851 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature