膈下迷走神经切断降低LPS所致大鼠发热及室旁核神经元放电频率

SUBDIAPHRAGMATIC VAGOTOMY REDUCES THE RESPONSES OF FEVER AND DISCHARGE OF NEURONS IN PVN TO LPS

目的 :探讨迷走神经是否可以作为LPS信息由外周组织传入中枢神经系统的桥梁。方法 :将Wistar大鼠随机分组 ,实验组为膈下迷走神经切断并给予LPS组 ,三个对照组为假手术生理盐水组 ,假手术LPS组 ,膈下迷走神经切断生理盐水组。用数字体温检测仪测定大鼠体温。用玻璃微电极记录正常大鼠和膈下迷走神经切断大鼠给予LPS前后下丘脑室旁核的单位放电。结果 :体温变化 :实验组大鼠体温变化值与假手术LPS组相比明显降低 (P <0 .0 5 )。单位放电变化 :正常大鼠给予LPS后室旁核单位放电放电频率明显增加 ,膈下迷走神经切断大鼠给予LPS后室旁核单位放电频率无明显变化。结论

Aim: To study the possibility that responses of fever and discharge of neurons in PVN to intraperitoneal administration of LPS are mediated by vagal afferents. Methods: Rectal temperature of rat was detected by digital temperature detecting instrument. Glass micropipette placed in PVN was used to record unit discharges of neurons in it, before and after LPS was injected into PVN in normal rats and vagotomy rats. Results: The rectal temperature change value in vagotomy LPS group was significantly decreased compared with that in sham LPS group, and there was striking difference between them( P <0.05). The discharges of neurons in PVN was increased in the normal rat in response to LPS. The discharges of neurons in PVN had no significant change in the vagotomy rats in response to LPS. Conclusion: The results indicate that vagus nerve may be one of the pathways of peripheral LPS signal communicating to CNS.