【摘要】 [目的]探讨在清醒大鼠诱发急性低血压对前庭内侧核(MVN)区pERK1/2表达的影响.[方法]股动脉插管观察大鼠血压,股静脉插管注射给予硝普钠(SNP)诱发急性低血压,使血压下降约30%左右后,利用免疫组织化学方法观察MVN区pERK1/2表达的变化,并结合化学损伤单侧前庭器官观察可能的外周机制.[结果]股静脉注射给予清醒大鼠SNP诱发急性低血压后5,10,20,40 min时,双侧MVN区均可见明显的pERK1/2蛋白表达,而5,10 min时表达增多最明显,与对照组比较差异具有统计学意义.在单侧前庭器官损伤组(24 h)诱发急性低血压后的各个时间段,前庭器官损伤同侧MVN区pERK1/2阳性神经元的表达明显减少,但损伤对侧MVN区的pERK1/2表达明显增多.[结论]静脉注射给予清醒大鼠SNP诱发急性低血压可致MVN区兴奋,此作用可被破坏外周前庭器官所阻断.更多还原

【Abstract】 OBJECTIVE To study the effects of acute hypotension on expression of pERK1/2 in the medial vestibular nucleus(MVN) of conscious rats.METHODSThe blood pressure was recorded by inserting a catheter into femoral artery of all experimental rats after anesthesia.The acute hypotension was induced by injecting the sodium nitroprusside(SNP) into femoral vein to lower the blood pressure about 30%,and the expression of pERK1/2 was observed by immunohistochemistry with combining with observation of unilateral vestibular apparatus lesion to make the approach to possible periphery mechanism.RESULTSThe expression of pERK1/2 was significant in bilateral MVN of intact labyrinthine conscious rats following the SNP-induced acute hypotension at 5min,10min,20min and 40min,and was most significant at 5 min and 10 min points and there was statistically significant difference as compared with control group.But in the control group,few numbers of pERK1/2-immunoreactive neurons was expressed in the MVN.The expression of pERK1/2-possitive neurons was significantly decreased in the MVN zone of unilateral vestibular apparatus lesion group following the SNP-induced acute hypotension at each time stages as compared with the contralateral MVN zone.CONCLUSIONThe MVN zone is activated by acute hypotension induced by intravenous injecting the SNP in conscious rats,and this action could be eliminated by periphery vestibular apparatus lesion.更多还原