Premium
Expression of functional cannabinoid CB 2 receptor in VTA dopamine neurons in rats
Author(s) -
Zhang HaiYing,
Gao Ming,
Shen Hui,
Bi GuoHua,
Yang HongJu,
Liu QingRong,
Wu Jie,
Gardner Eliot L.,
Bonci Antonello,
Xi ZhengXiong
Publication year - 2017
Publication title -
addiction biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.445
H-Index - 78
eISSN - 1369-1600
pISSN - 1355-6215
DOI - 10.1111/adb.12367
Subject(s) - ventral tegmental area , nucleus accumbens , dopamine , cannabinoid , cannabinoid receptor , neuroscience , midbrain , chemistry , receptor , neuron , antagonist , pharmacology , medicine , endocrinology , biology , dopaminergic , central nervous system , biochemistry
We have recently reported the expression of functional cannabinoid CB 2 receptors (CB 2 Rs) in midbrain dopamine (DA) neurons in mice. However, little is known whether CB 2 Rs are similarly expressed in rat brain because significant species differences in CB 2 R structures and expression are found. In situ hybridization and immunohistochemical assays detected CB 2 gene and receptors in DA neurons of the ventral tegmental area (VTA), which was up‐regulated in cocaine self‐administration rats. Electrophysiological studies demonstrated that activation of CB 2 Rs by JWH133 inhibited VTA DA neuronal firing in single dissociated neurons. Systemic administration of JWH133 failed to alter, while local administration of JWH133 into the nucleus accumbens inhibited cocaine‐enhanced extracellular DA and i.v. cocaine self‐administration. This effect was blocked by AM630, a selective CB 2 R antagonist. These data suggest that CB 2 Rs are expressed in VTA DA neurons and functionally modulate DA neuronal activities and cocaine self‐administration behavior in rats.