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Acupuncture has been introduced as one of the available therapies widely used in alternative medicine, but it has not achieved widespread acceptance with scientific evidence. Furthermore there are still many unanswered questions about the basic mechanisms of acupuncture. To investigate the neuropharmacological mechanisms of oriental acupuncture, we studied the acupuncture-induced changes of in vivo monoamine release in the rat brain. A microdialysis guide cannula was implanted into the nucleus accumbens (ACC), which plays an important role in the brain reward system. Acupuncture treatment at the unilateral or bilateral Shenshu (bladder urinary channel 23) acupoints, located on the both sides of the spinous processes on the lower back, was carried out for 60 min in freely moving rats, and the dopamine (DA) and serotonin (5-HT) contents of the microdialysates in the ACC were measured simultaneously. In rats subjected to acupuncture at bilateral Shenshu acupoints, increases of 5-HT release in the ACC were observed at 20 min of acupuncture treatment and continued until 40 min after acupuncture was ended. Acupuncture at a unilateral Shenshu acupoint increased the release of 5-HT at 20 min compared with that in the sham-control group. Five-HT release returned to the baseline level at 120 min. The effects of acupuncture at bilateral Shenshu acupoints on the release of 5-HT in the ACC were greater than that of unilateral acupuncture treatment. In contrast, DA release in the ACC was not changed following acupuncture treatment. Effective acupuncture increased and prolonged the activity of serotonergic neurons in the reward system pathway of the brain. This suggests that oriental acupuncture therapy may be effective for the treatment of emotional disorders, drug abuse and alcoholism.

Alterations in cerebral monoamines following application of electroacupuncture were investigated using conscious rats with and without application of restraining stress. The dopamine and serotonin levels were significantly decreased in the nucleus accumbens, caudate putamen, and lateral hypothalamus and increased in the dorsal raphe nucleus by restraining stress. On the other hand, application of electroacupuncture on the lumbar and hindlimb segments eliminated the above changes in dopamine, while the changes in serotonin were attenuated by lumbar and hindlimb electroacupuncture. However, the effects of hindlimb electroacupuncture were greater than those of lumbar electroacupuncture. These results clearly indicate that lumbar and hindlimb electroacupuncture stimulations have differential effects on brain monoaminergic neurons in rats exposed to restraining stress. Moxa burning stimulation was applied to the lumbar and hindlimb segments of rats without restraining stress. The dopamine level was significantly increased in the midbrain substantia nigra-ventrotegmental area by hindlimb moxibusion. On the other hand, the serotonin levels were significantly increased in the nucleus amygdala by lumber moxibusion and decreased in the nucleus accumbens by hindlimb moxibusion. The present results indicate that electroacupuncture applied to the lumbar and hindlimb segments has an antistress effect, while the application of moxibustion to the lumbar and hindlimb segments was likely to stimulate the functions of mesocortical and mesolimbic dopaminergic and serotonergic neurons. We suggest that functional alterations in cerebral dopaminergic and serotonergic neurons are involved in the clinical efficacy of electroacupuncture and moxibustion, especially because of their antistress and psychosomatic actions.

These findings suggest that EAC applied at ST 36 (Tsu-San-Li) was more effective for reducing the increased alcohol-drinking behavior in restricted rats, and they showed that a point specific in EAC procedure was associated with an increase of striatal DA levels. These findings provide new information for understanding alcohol-drinking behavior and for treating human alcoholics.

The findings suggested that an abnormality of the dopaminergic neurons in the ACC that are involved with DAT dysfunction is associated with the development of alcohol tolerance.

The findings suggested that an abnormality of the dopaminergic neurons in the ACC that are involved with DAT dysfunction is associated with the development of alcohol tolerance.

Background: Although a number of studies on traditional eastern or Chinese medicine, such as acupuncture, moxibustion, and herbal drugs, have been reported, few reports describe electroacupuncture (EAC) effects on drug-and alcohol-seeking behaviors in animal models. The purpose of the present study was to investigate the effect of EAC on changes in alcohol-drinking behavior in rats challenged with restriction and immobilization stress.Material and Methods: Male Sprague Dawley® rats (260 -280 g) were tightly hung and immobilized in restriction models for 10 min. These immobilization stresses were performed twice a week for 1 week and for 3 consecutive weeks for the short-and long-restricted stress groups, respectively. EAC was applied for 10 min to the hindlimb point, Tsu-San-Li (ST 36), and the lumbar point, Shen-Shu (BL 23). These points are used to treat mental and psychosomatic disorders and are known clinically to produce a sedation effect. Time-access alcohol-drinking behavior was determined at 24 hr after the termination of EAC. Finally, brain dopamine (DA) levels were assayed in the two groups. A sham-control group underwent only restricted stress without EAC.Results: Time-access alcohol-drinking behavior increased significantly in the long-restricted group compared with the short-restricted group and controls. EAC applied to the ST 36 (Tsu-San-Li) point suppressed the increased alcohol-drinking behavior in restricted rats. However, EAC applied to the Shen-Shu (BL 23) point was not effective, because alcohol-drinking behavior was significantly increased in longrestricted rats compared with short-restricted rats. Striatal DA levels of restricted rats with EAC stimulated at Tsu-San-Li were increased significantly compared with the rats with EAC applied to the Shen-Shu point.Conclusion: These findings suggest that EAC applied at ST 36 (Tsu-San-Li) was more effective for reducing the increased alcohol-drinking behavior in restricted rats, and they showed that a point specific in EAC procedure was associated with an increase of striatal DA levels. These findings provide new information for understanding alcohol-drinking behavior and for treating human alcoholics.

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