Data from: Sex-specific gene expression in the mouse nucleus accumbens before and after cocaine exposure

Females are more sensitive than males to the addictive effects of cocaine
and are more likely to relapse. The nucleus accumbens has a
well-established major role in the response to cocaine, and sex-specific
differential expression of key transcripts at baseline and after cocaine
withdrawal could underlie some of these differences. To address this
hypothesis, four groups of mice (cycling females, ovariectomized females
treated with estradiol or placebo and males) were evaluated for open field
activity following 7 daily injections of saline or cocaine. Sensitization
to the locomotor effects of cocaine was most pronounced in ovariectomized
mice receiving estradiol, was greater in cycling females than in males,
and failed to occur in ovariectomized/placebo mice. After a 28-day period
of withdrawal, RNA prepared from the nucleus accumbens of individual
cocaine or saline injected mice was subjected to RNASeq analysis.
Expression of a substantial fraction of the transcripts expressed in the
nucleus accumbens (~3%) differed in cycling female mice when compared to
male mice, was altered by ovariectomy or was responsive to estradiol
treatment. The transcripts differentially expressed in the nucleus
accumbens of cycling female mice withdrawn from cocaine for 28-days
exhibited substantial overlap with those differentially expressed in the
nucleus accumbens of male mice withdrawn for 7-days. A small set of
transcripts were similarly affected by cocaine in placebo or estradiol
treated ovariectomized mice. Transcripts differentially expressed after
28-days of withdrawal encoded neprilysin, which degrades enkephalin and
other neuropeptides, G protein coupled receptors and secreted proteins
such as Wnt2, Fst and Igfbp4.