Abstract: Objective To study the changes and actions of neuronal constructive nitric oxide synthase(nc-NOS) in heroin drug abuse. Methods The expression of ncNOS and ncNOS mRNA in neurons of cerebral cortex,periaqueductal gray matter and the ventral tegmental area was observed by immunohistochemistry,in situ hybridization and image analysis technique after heroin dependence and spontaneous withdrawal in rats. Results The quantity of ncNOS and ncNOS mRNA rised clearly and the number of ncNOS and ncNOS mRNA positive cells increased greatly in heroin dependence and withdrawal. The changes of ncNOS and ncNOS mRNA in spontaneous withdrawal were more clear than ones of dependence. Heroin dependence and withdrawal led to alterations in ncNOS and ncNOS mRNA expression in important regions implicated in the physical tolerance and dependence. Conclusion The ncNOS plays an important role in heroin dependence and withdrawal. The ncNOS immunohistochemical changes observed in the present study might be useful for the forensic pathological diagnosis of heroin drug abuse.

Key words: heroin, drug abuse, ncNOS, immunohistochemistry, in situ hybridization