The medial preoptic area modulates cocaine-induced locomotion in male rats

Abstract

Cocaine-induced locomotion is mediated by dopamine in the nucleus accumbens (NAc). Recent evidence indicates that the medial preoptic area (mPOA), a region in the rostral hypothalamus, modulates cocaine-induced dopamine in the NAc. Specifically, rats with lesions of the mPOA experienced a greater increase in dopamine following cocaine administration than rats with sham lesions. Whether the mPOA similarly influences cocaine-induced locomotion is not known. Here we examined whether radiofrequency or neurotoxic lesions of the mPOA in male rats influence changes in locomotion that follow cocaine administration. Locomotion was measured following cocaine administration in male rats with neurotoxic, radiofrequency, or sham lesions of the mPOA. Results indicate that bilateral lesions of the mPOA facilitated cocaine-induced locomotion. This facilitation was independent of lesion type, as increased locomotion was observed with either approach. These findings support a role for the mPOA as an integral region in the processing of cocaine-induced behavioral response, in this case locomotor activity.

Rapid effects of ovarian hormones in dorsal striatum and nucleus accumbens

“…The medial preoptic area (MPOA) may regulate some of the effects of estradiol on ventral striatal DA activity. ER positive cells in the MPOA have been shown to project to the VTA, and inhibit DA release in the NAc (Will et al, 2016). The effect of estradiol on DA release in response to cocaine was diminished after lesions of the MPOA, and estradiol microinjections in the MPOA enhanced cocaine induced DA release in female rats (Tobiansky et al, 2015).…”