大鼠伏隔核多巴胺D2受体及转运体与吗啡条件性位置偏爱易感性的关系

Objective To explore the possible role of the expression of dopamine D2 receptor (D2R)and dopamine transporter(DAT)located in the nucleur accumben(Nac)in rats with difierent CPP susceptibility.Methods Altogether 160 male Sprague-Dawley rats were randomly assigned into experiment group(n=130)and control group(n=30).The experiment rats were re-classified into three groups according to the numerical value of the CPP(conditioned place preference),high preference group(HP group,n=26),moderate preference group(n=78)and low preference group(LP group,n=26).At the time of 3 hours,72 hours and 14 days after the final injection,rats in each group were scarified,and the mRNA levels of D2R and DAT in Nac were estimated with in situ hybridization.Results No significant difference of pretest scores staying at the non-preference chamber exist among the three groups(P=0.470),however.the time stayed at the conditioned preference chamber during the test period minus the time stayed at pretest natural preference was significantly higher in the HP group than the LP group(P＜0.01).In each time-point,the expression of D2R mRNA in HP group,were lower that in LP group(131±3,122±5,119±5)and(125±4,117±8,114±5),P＜0.01].In each time-point,the expression of DAT mRNA in HP group,were significantly lower than that in LP group(161±5,143±4,134±6)and(156±5,139±3,130±4),P＜0.01].Conclusions It can be inferred that D2R and DAT may be correlated closely and underlie the difierent susceptibility to morphine induced CPP.

The role of dopamine D2 receptor and transporter in nucleur accumben in different susceptibility of morphine-induced conditioned place preference in rats