Effects of heroin dependence on the expression of DBH and CCK in the VTA and NAc regions of rat brain

Abstract

To investigate the effect of the heroin addicts on rat's DβH‐, CCK‐immunoreactive cells in the ventral tegmental area(VTA) and nucleus accumbens(NAc) regions, and exploring the effect of heroin dependence on regulation of dopamine release and self‐protective mechanism in brain. Adulthood 55 male SD rats were randomly divided into normal control group(NCG), saline control group(SCG) and the heroin‐dependent group(HDG). Heroin‐dependent rat models were set up by the way of subcutaneous injection of heroin and brain tissues are excised on the 10th, 17th, 24th, 31th, and 38th days after models are set up. Immunohistochemical staining was performed to test the expression of DβH and CCK in the VTA and NAc regions. The expression of DβH and CCK was observed as brown yellow particle in the cytoplasm of neurons in the VTA and NAc regions. The expression of DβH‐ immunoreactive cells is down‐regulated, while the expression of CCK‐immunoreactive cells is up‐regulated in the VTA and NAc regions from HDG rats than that from SCG and NCG rats at different time points. The results suggest that the secretion of DβH is inhibited during heroin dependence, and it might be one reason causing dopamine increase in VTA and NAc. The increased secretion of CCK in VTA and NAc might be self‐protective mechanism in brain.Grant sponsor(s): NSFC(Natural Science Foundation of China)Grant number(s):81060110Grant Funding Source: Natural Science Foundation of China