次声作用后鼠脑CA1区mGluR1α表达改变及其拮抗剂MCPG的作用研究

摘要

为探讨次声作用后鼠脑CA1区mGluR1α表达改变规律，并观察mGluR1α拮抗剂MCPG的作用。将120只SD大鼠随机分为次声作用组及MCPG治疗组，两组再分为对照组及次声作用1、7、14次组，每组15只。用8Hz 130dB的次声按规定次数，每次作用2h。免疫细胞化学染色，光镜、透射电镜观察形态改变。结果显示：次声作用1次组mGluR1α阳性细胞数即出现变化（P＜0.05）；7次组表达最为显著（P＜0.01）；14次组减少至正常水平。MCPG治疗组mGluR1α阳性值与等数次声组之间无差异（P＞0.05）。形态学研究证实，MCPG对神经元有明显保护作用。提示次声作用可通过mGluR1α介导兴奋性神经毒作用，mGluR1α活性改变是导致次声性脑损害的因素之一。%To study the change in mGluR1α in CA1 after infrasonic damage and the effect of its antagonist MCPG,120 SD rats were randomizied into infrasonic damage group and MCPG therapy group.The two groups were subdivided into control group and 1-challenge, 7-chellenges, 14-challenge groups respectively,each group consisted of 15 rats. Rats were exposed to 8Hz 130dB infrasound as designed,2h for each challenge.The mGluR1α was stained by immunohistochemistry method.The changes in mGluR1α and cell pattern were observed under light and electronic microscopes.The results showed the number of mGluR1α positive neurons increased after 1-challenge infrasonic damage(P＜0.05)；and in the 7-challenge group was most obvious(P＜0.01)；in the 14-challenge group,it decreased to normal level.The change of mGluR1α in MCPG therapy groups was as that in infrasonic damage groups(P＞0.05).MCPG had an effect to protect neuron from infrasonic damage as identified by morphology.It is concluded that the change of mGluR1α activity could mediate excitotoxicity and was one of the major factors related with neuron injury after infrasound.