Association of different susceptibilities to morphine with the expression of 5-HTT and 5-HT1AR mRNA in brain regions of SD rats / 中南大学学报(医学版)

ABSTRACT

Objective To investigate the possible mechanism for the different CPI susceptibili-ties. Methods Using a conditioned place preference (CPP) model, rats were selected into high and low preference groups. Using in situ hybridization, we examined the mRNA expression of 5-hydroxytryptamine transporter (5-HTT) and 5 -hydroxytryptamine 1 A receptor (5-HT1 AR) in 3 cruci-al regions in addiction, namely the ventral tegmental area (VTA) , the nucleus accumbens (NAc) ,and the medial prefrontal cortex (mPFC) , during the dependence and withdrawal. Results During dependence state, the expression of 5-HTT mRNA in each of the regions in the high preference group was significantly lower than that of the low preference group, while higher expression of 5-HT1AR mRNA in each of the regions in the high preference group than that of the low preference group was found (P<0.05). During withdrawal state, the expression of 5-HTT mRNA in each of the regions in high preference group was significantly higher than that of the low preference group, while lower expres-sion of 5-HTIAR mRNA in each of the regions in the high preference group than that of the low prefe-rence group was found (P<0.05). Conclusion 5-HTT and 5-HT1 AR may play a role in diffe-rences in susceptibility to morphine.