药物成瘾行为的脑机制及其研究进展

DRUG ADDICTION BEHAVIOR AND ITS POTENTIAL BIOLOGICAL MECHANISM

药物成瘾是脑内相关核团和细胞在药物反复作用下发生适应性变化的时间依赖过程。成瘾的适应性学说从ｃＡＭＰ水平调节、阿片和多巴胺受体与Ｇ蛋白家族耦联等方面，为成瘾形成机制提供了最基本的生物学范畴的理论解释。实验证据在一定程度上揭示了从给药到耐受、敏感、依赖，再到撤药症状的生物变化过程。然而，阐明从急性给药到特殊脑区持续性的适应机制仍然是当前成瘾研究最具挑战性的目标之一。

Drug addiction is a time-dependent course during which specific nucleus or cells in the brain adapt to repeated exposure to the drugs. The possible mechanism of addiction is explained basically and biologically by adaptation of cAMP pathway signaling, opioid and DA receptor-G protein coupling, etc. Biological changes from the acute effects of drugs to tolerance, sensitization, dependence and withdrawal syndromes have been revealed by much evidence. But at present it is still one of the greatest challenges to explicate the mechanism of long-term adaptation in specific brain regions.