BLOCKADE OF INTERLEUKIN-1 INDUCED HYPERTHERMIA BY SUBDIAPHRAGMATIC VAGOTOMY - EVIDENCE FOR VAGAL MEDIATION OF IMMUNE BRAIN COMMUNICATION

Interleukin-1 beta (IL-1 beta), a cytokine released by activated immun e cells, elicits various illness symptoms including hyperthermia. Prev ious hypotheses to account for these actions have focused on blood-bor ne IL-1 beta exerting its effects directly at the level of the brain. However, recent behavioral and physiological evidence suggest that IL- 1 beta can activate the subdiaphragmatic vagus. The present experiment s demonstrate that subdiaphragmatic vagal transection disrupts the hyp erthermia-inducing effects of recombinant human IL-1 beta and stress. These data provide evidence for a novel route of immune-brain communic ation, as well as a novel route whereby stress can influence physiolog ical processes.