Arginine vasopressin (AVP)has been shown to have significant effects on the thermoregulation. The present experirnents were to investigate the effect of electroacupuncture(EA) on the discharge activity of temperature-sensitive neurons of preoptic-anterior hypothalamus (PO-AH) in rabbits treated by AVP and arginine vasopressin monoclonal antibody(AVPMcAb). The results were as follows: (1) AVP could markedly promote the firing activity of EA on heat-sensitive neurons in PO-AH. (2) AVPMcAb could markedly reduce the effect of EA on temperature-sensitive neurons in PO-AH.Experimental results indicated that the mechanisms of EA on hypothermia might be related to AVP