Effects of acupuncture on monoamine neurotransmitters in raphe nuclei in obese rats

Effects of acupuncture on the levels of neurotransmitters in the raphe nuclei were investigated in obese rats. It was found that the levels of tryptophan (Trp) and 5-hydroxyindoleacetic acid (5-HIAA) were increased, and 5-hydroxytryptamine (5-HT) level and 5-HT/5-HIAA ratio decreased in the raphe nuclei of the obese group as compared with the normal group; and that acupuncture could produce weight reduction, increase the 5-HT level and 5-HT/5-HIAA ratio, and decrease the contents of Trp and 5-HIAA, but did not change the levels of dopamine (DA) and noradrenaline (NA). It is indicated that benign regulative action of acupuncture on 5-HT and its metabolism in the raphe nuclei is possibly one of the factors for reducing weight by acupuncture.