Effects of kainic acid on body temperature of rats: role of catecholaminergic and serotonergic systems.

Intraventricular (IV) administration of doses of 0.1 microgram kainic acid caused diphasic effects on the body temperature of rats--initially hypothermia, rapidly followed by hyperthermia. Pretreatment of rats with 6-OHDA effectively blocked the hypothermic and significantly increased the hyperthermic effects of kainic acid. The hyperthermic effect of kainic acid was reversed in the 5,6-DHT- and dorsal raphe-lesioned rats. However, the electrolytic lesion of the medial raphe nucleus did not cause any changes in the thermic activity of kainic acid. The thermic effects of kainic acid injected IV appear to be dependent on the balance between serotonergic and catecholaminergic influences on central thermoregulation.