HYPOTHERMIA ATTENUATES THE NORMAL INCREASE IN INTERLEUKIN-1-BETA RNA AND NERVE GROWTH-FACTOR FOLLOWING TRAUMATIC BRAIN INJURY IN THE RAT

Significant morbidity and mortality associated with traumatic brain in jury(TBI) are allied with secondary posttrauma inflammatory complicati ons, Hypothermia has been suggested as a possible treatment to lessen or suppress these inflammatory reactions, We report here that interleu kin 1 beta, a cytokine responsible for initiating inflammatory cascade s, is elevated in rat cortex within 6 h of TBI in the rat, Nerve growt h factor (NGF) RNA and protein also increased subsequently, and NGF pr otein remained elevated for up to 7 days, Four hours of whole body hyp othermia (32 degrees C), applied immediately after the TBI, attenuated the posttrauma increase in IL-1 beta RNA and eliminated the increase in NGF RNA and protein observed in cerebral cortex following TBI, Thus , hypothermia may be an effective therapy to diminish the posttrauma i nflammatory cascade in the brain (as suggested by the decrease in IL-1 beta), However, the same treatment may hinder the brain's intrinsic r epair mechanisms, Optimal treatment may, therefore, require supplement al administration of neurotrophic factors or other agents along with h ypothermia.