Demetrikopoulos M K, Siegel A, Schleifer S J, Obedi J, Keller S E
Department of Neurosciences, Graduate School of Biomedical Sciences, UMDNJ, Newark 07103.
Brain Behav Immun. 1994 Sep;8(3):218-28. doi: 10.1006/brbi.1994.1020.
This study examined the effects of dorsal midbrain periaqueductal gray (PAG) stimulation on both splenic and peripheral blood natural killer (NK) cell function as well as the proliferative response of lymphocytes to phytohemagglutinin mitogen. Male Sprague-Dawley rats were implanted with bipolar electrodes in the dorsal PAG. Following recovery, bipolar electrical stimulation eliciting a flight response was delivered at the rate of one/min for 30 min to freely moving rats. While dorsal PAG stimulation did not alter mitogen response or splenic NK activity, stimulation of this region of the PAG produced a marked decrease in peripheral blood NK response. In order to begin to explore a possible mechanism regulating suppression of peripheral blood NK activity, naltrexone (10 mg/kg) was administered prior to dorsal PAG stimulation. The results of this experiment replicated the findings that demonstrated suppression of peripheral blood NK following dorsal PAG stimulation. Naltrexone did not effect PAG induced suppression of peripheral blood NK. These findings point to the importance of the dorsal aspect of the PAG in the regulation of peripheral blood NK activity and further suggest that this phenomenon may not be opioid mediated.
本研究考察了中脑导水管周围灰质（PAG）背侧刺激对脾脏及外周血自然杀伤（NK）细胞功能的影响，以及淋巴细胞对植物血凝素丝裂原的增殖反应。将雄性Sprague-Dawley大鼠的PAG背侧植入双极电极。恢复后，以每分钟1次的频率对自由活动的大鼠进行30分钟双极电刺激，引发逃避反应。虽然PAG背侧刺激未改变丝裂原反应或脾脏NK活性，但对该区域的刺激使外周血NK反应显著降低。为了开始探索调节外周血NK活性抑制的可能机制，在PAG背侧刺激前给予纳曲酮（10毫克/千克）。该实验结果重复了此前表明PAG背侧刺激后外周血NK受抑制的研究发现。纳曲酮未影响PAG诱导的外周血NK抑制。这些发现表明PAG背侧在调节外周血NK活性方面的重要性，并进一步表明该现象可能不是由阿片类物质介导的。
