Fundamental Sex Differences in Cocaine-Induced Plasticity of Dopamine D1 Receptor- and D2 Receptor-Expressing Medium Spiny Neurons in the Mouse Nucleus Accumbens Shell.

Background: Cocaine-induced plasticity in the nucleus accumbens shell of males occurs primarily in dopamine D receptor-expressing medium spiny neurons (D1R-MSNs), with little if any impact on dopamine D receptor-expressing medium spiny neurons (D2R-MSNs). In females, the effect of cocaine on accumbens shell D1R- and D2R-MSN neurophysiology has yet to be reported, nor have estrous cycle effects been accounted for.

Methods: We used a 5-day locomotor sensitization paradigm followed by a 10- to 14-day drug-free abstinence period.