It is well known that the preoptic area(POA)of hypothalamus,containing temperature-sensitive and-insensitive neurons,plays an important role in precise thermoregulatory responses.Whereas arginine vasopressin(AVP)has been shown to induce hypothermia by increasing the firing activity of warm-sensitive neurons and decreasing it of cold-sensitive and temperature-insensitive neurons,the effects of AVP on GABAergic synaptic transmission in POA remain to be determined.