Given the central role of the AcbC in behaviors related to impulsivity and drug addiction20, 21, our next goal was to identify molecular underpinnings of SHRs’ impulsive predisposition. Of the genes related to synaptic plasticity and neurotransmission included in our expression panel, the transcription factor Crem showed the greatest difference (t10=3.62, p=0.005, Fig. 2a, Supplementary Table 1). The decrease, specific to the AcbC (Fig. 2a inset), was verified using an independent qRT-PCR assay (t10=3.31, p=0.008) and reproduced in a separate cohort of animals (t15=2.22, p=0.042). Interestingly, acute heroin (1 mg/kg, ip) increased Crem mRNA expression in the AcbC of SHRs (t10=8.54, p<0.001) but not WKYs (t9=0.172, p>0.05), while Crem was equally induced in the AcbSh of both strains (Fig. 2b).
