CROSS-TOLERANCE TO ENVIRONMENTAL-STRESS AND ENDOTOXIN

Mild DIC-like phenomena develop in rodents exposed to environmental st ress, induced by prolonged fluctuation in ambient temperature, known a s SART (specific alternation of rhythm in temperature) stress, the sym ptoms being essentially similar to those produced by endotoxin. The ai m of the present study was to investigate whether common mechanisms ar e involved in the stress-induced DIC-like phenomena and endotoxaemia. The mortality in mice after intraperitoneal injection with endotoxin a t 8.3, 16.7 and 33.3 mg/kg increased in a dose-dependent manner. In th e mice exposed to stress for 7 days, the death rate following endotoxi n at 8.3 mg/kg was markedly lower than that in unstressed mice, althou gh no difference was detected between the two groups following endotox in at 16.7 and 33.3 mg/kg. Conversely, repeated administration of endo toxin at a low dose, 0.5 mg/kg, during exposure to stress for 7 days i nhibited the stress-induced thrombocytopenia and hypofibrinogenemia. T hese findings indicate the development of cross tolerance to prolonged environmental stress and endotoxin, implying involvement of a common mechanism. (C) 1998 Elsevier Science Inc.