Glycogen synthase kinase 3beta in the nucleus accumbens core mediates cocaine-induced behavioral sensitization.

Glycogen synthase kinase 3beta (GSK-3beta) is a ubiquitous serine/threonine protein kinase involved in a number of signaling pathways. Previous studies have demonstrated a role for GSK-3beta in the synaptic plasticity underlying dopamine-associated behaviors and diseases. Drug sensitization is produced by repeated exposure to the drug and is thought to reflect neuroadaptations that contribute to addiction. However, the role of GSK-3beta in cocaine-induced behavior sensitization has not been examined. The present study investigated the effects of chronic cocaine exposure on GSK-3beta activity in the nucleus accumbens (NAc) and determined whether changes in GSK-3beta activity in the NAc are associated with cocaine-induced locomotor sensitization. We also explored whether blockade of GSK-3beta activity in the NAc inhibits the initiation and expression of cocaine-induced locomotor sensitization in rats using systemic or brain region-specific administration of the GSK-3beta inhibitors lithium chloride (LiCl) and SB216763. GSK-3beta activity in the NAc core, but not NAc shell, increased after chronic cocaine (10 mg/kg, i.p.) administration. The initiation and expression of cocaine-induced locomotor sensitization was attenuated by systemic administration of LiCl (100 mg/kg, i.p.) or direct infusion of SB216763 (1 ng/side) into the NAc core, but not NAc shell. Collectively, these results indicate that GSK-3beta activity in the NAc core, but not NAc shell, mediates the initiation and expression of cocaine-induced locomotor sensitization, suggesting that GSK-3beta may be a potential target for the treatment of cocaine addiction.

Traditional Chinese medicine in treatment of opiate addiction.

Traditional Chinese medicine (TCM) includes Chinese medicine and acupuncture. Chinese medicine consists of natural products including plants, animals and minerals. TCM has been practiced in China for more than 2000 years, and for the past 200 years has been used in treatment of drug addiction. Ten Chinese medicines for the treatment of opiate addiction have been approved by the Chinese State Food and Drug Administration (SFDA), and at least 6 are in clinical trials. The general therapeutic principle of Chinese medicine developed was based on its unique theory of " reinforcing healthy Qi and resolving and removing effects of toxicity". Acupuncture, another essential part of TCM, which was developed based on the principle that " functions of the human body are controlled by the ' Jing-Luo' and 'Qi-Xue'system" , has been used not only in China, but also in Europe, the USA and other countries, for controlling opiate addiction. There are some advantages in using TCM for opiate detoxification, including less harmful side effects, high safety and ideal effects in the inhibition of protracted withdrawal symptoms and relapse. Co-administration of TCM with modern medicine shows some synergistic effects in detoxification. Many TCM for detoxification also have efficacy in the rehabilitation of abnormal body functions induced by chronic drug use, including improving immune function, increasing working memory and preventing neurological disorder. Given that TCM is effective in the prevention of relapse and causes fewer side effects, it may be used widely in the treatment of opiate addiction.