Neuroendocrine mechanism of stress-induced immunosuppression and roles of cytokines.

各种类型的应激抑制免疫活动。在此之前，我们已经证实了交感神经系统（SNS）在应激诱导的免疫抑制中的重要作用。在这项研究中，我们研究了脑刺激对大鼠交感神经介导的免疫抑制的影响。当腹内侧下丘脑（VMH），一个假定的下丘脑中枢连接到SNS，电刺激，脾淋巴细胞的增殖活性降低。VMH的抑制作用不受肾上腺切除术的影响，但被神经节阻滞和手术交感神经切除所取消。这些结果表明VMH在应激诱导的免疫抑制中起着关键作用。当脑室内给予白细胞介素-1（IL-1）（免疫细胞和脑细胞中产生的代表性细胞因子）时，也观察到类似的抑制作用。还发现脑IL-1可加速各种外周器官中去甲肾上腺素的周转，这意味着SNS的活性增加。有报道称，颅内注射抗IL-1抗体可减弱应激诱导的免疫抑制。总之，脑IL-1和VMH在应激诱导的免疫抑制中起重要作用。

Various types of stressor suppress immune activities. Previously, we have confirmed a significant role of the sympathetic nervous system (SNS) in the stress-induced immunosuppression. In this study, we examined the effects of brain stimulation on the sympathetically mediated immunosuppression in rats. When the ventromedial hypothalamus (VMH), a putative hypothlamic center linked to the SNS,was stimulated electrically, the proliferative activity of splenic lymphocytes was reduced. The suppressive effect of VMH was not affected by adrenalectomy, but abolished by ganglionic blockade and surgical sympathetic denervation. These results suggest a critical role of the VMH in the stress-induced immunosuppression. Similar suppressive effects were also observed when interleukin-1 (IL-1), a representative cytokine produced in immune cells and brain cells, was given intracerebroventricularly. Brain IL-1 was also found to accelerate noradrenaline turnover in various peripheral organs, implying increased activity of the SNS.There are reports that the stress-induced immunosuppression was attenuated by intracranial injection of anti-IL-1 antibody. Collectively, it was concluded that brain IL-1 and the VMH play important roles in the stress-induced immunosuppression.