The role of cytokines in heat stroke.

Heat stroke is a disease characterized by high fever. Cytokines such as interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-delta) play a major role in fever production. In the current studies, eight patients with heat stroke were enrolled in a cytokine studies. Serum cytokine levels of these patients were determined by EIA methods, and in vitro IL-1 and IL-1 inhibitor production were determined by murine thymocyte proliferation assay and/or EIA. Significantly high levels of circulating IL-1, TNF-delta, and IL-6 were demonstrated. Positive correlations were demonstrated between the body temperature and the level of IL-1 beta, and the cooling time and level of serum IL-1 beta. In addition, monocytes from heat stroke patients after complete recovery, secreted a much higher amount of IL-1 than did normal volunteers. However, there was no difference in IL-1 inhibitor production. These results indicate that cytokines may play a major role in the pathogenesis of heat stroke, and the ability to make different amounts of IL-1 in response to exogenous stimulation appear to be risk factors for an attack of heat stroke.