Brain interleukin-1 as a mediator of stress responses

外周免疫功能受到各种应激因素的影响，但应激诱导的免疫调节机制尚不清楚。脑白细胞介素-1（IL-1）参与了应激诱导的肾上腺皮质激活。本研究以大鼠和小鼠为实验动物，探讨了脑IL-1在应激诱导的免疫调节中的可能作用。当小鼠和/或大鼠进行制动应激，血清IL-6水平上升，在1小时后，在肝脏和脾脏中的IL-6 mRNA的表达增加。肝组织免疫组化结果显示，应激诱导的IL-6主要分布于肝实质细胞。当将抗IL-1的抗体注入脑室时，血清IL-6对应激的反应大大减弱，但通过侧脑室注射微量IL-1来模拟。应激后即刻脑IL-1 mRNA水平升高。从这些结果中，我得出结论，外周IL-6响应制动应力介导的脑IL-1。

Peripheral immune functions are modified by various stressors, but the mechanisms of the stress-induced immunomodulation are poorly understood. There have been reports that brain interleukin (IL)-1 is involved in the stress-induced adrenocortical activation, In this study, I have investigated about possible roles of brain IL-1 in the stress-induced immunomodulation using rats and mice as experimental animals. When mice and/or rats were subjected to immobilization stress, the serum IL-6 level rose in 1 hr, following increased expression of IL-6 mRNA in both the liver and the spleen. Immunohistochemical examinations of liver tissue revealed that the stress induced IL-6 mainly in hepatic parenchymal cells. The serum IL-6 response to the stress was much attenuated when an antibody against IL-1 was injected into the cerebral ventricle, but mimicked by an intracerebroventricular injection of minute amounts of IL-1. It was also found that the brain IL-1 mRNA level rose immediately after the stress. From these results, I conclude that the peripheral IL-6 response to immobilization stress is mediated by brain IL-1.