摘要
目的观察辣椒素对大鼠脊髓背角中磷酸化环磷酸腺苷反应元件结合蛋白(pCREB)表达的影响,探讨延髓外侧网状核(LRN)对心脏伤害性感受的下行紧张性调控作用。方法将30只雄性Sprauge Dawley大鼠随机分为空白组、溶媒组、辣椒素组、LRN电损毁组和LRN电损毁+辣椒素组,每组6只。空白组大鼠麻醉后不做手术处理,其余各组大鼠均行心包内插管术,LRN电损毁组和LRN电损毁+辣椒素组大鼠于心包内插管术后行双侧LRN电损毁。各组大鼠心包插管1 h后,回抽心包积液,溶媒组大鼠心包内注射0.2 mL溶媒(含有0.1 mL的吐温80和0.1 mL无水乙醇),辣椒素组和LRN电损毁+辣椒素组大鼠心包内注射0.2 mL辣椒素(0.01 g·L-1),LRN电损毁组大鼠心包内不注射任何溶液。心包内注射药物的同时,记录大鼠背斜方肌超出基线活动10%的肌电(EMG)反应数目,空白组于维持麻醉1 h后记录EMG反应数目。各组大鼠经心包内注射药物30 min后,灌注固定液并取T3~T5脊髓,采用免疫组织化学染色法检测各组大鼠脊髓背角中pCREB免疫阳性细胞数目。结果空白组、溶媒组、LRN电损毁组大鼠背斜方肌无超出基线活动10%的EMG反应。辣椒素组和LRN电损毁+辣椒素组大鼠背斜方肌EMG反应数目和脊髓背角中pCREB免疫阳性细胞数目均显著高于空白组、溶媒组和LRN电损毁组(P<0.05)。LRN电损毁+辣椒素组大鼠背斜方肌EMG反应数目和脊髓背角中pCREB免疫阳性细胞数目均显著高于辣椒素组(P<0.05)。结论大鼠心包内注射辣椒素能诱发背斜方肌EMG反应且脊髓背角中pCREB免疫阳性细胞数目增加。LRN对大鼠心脏伤害性感受具有下行紧张性抑制作用。
Objective To observe the effect of capsaicin on the expression of phosphorylated cyclic adenosine monophosphate response element binding protein(pCREB)in the spinal dorsal horn of rats,and explore the downward-tension regulation of the lateral medullary reticular nucleus(LRN)on heart injury sensation.Methods Thirty male Sprauge Dawley rats were randomly divided into blank group,vehicle group,capsaicin group,LRN electrical damage group and LRN electrical damage+capsaicin group,with 6 rats in each group.The rats in the blank group were not operated after anesthesia.The rats in the other groups underwent intrapericardial intubation.The rats in the LRN electrical damage group and LRN electrical damage+capsaicin group received bilateral LRN electrical damage after endopericardial intubation.One hour after the pericardial intubation of rats in each group,the pericardial effusion was withdrawn,and 0.2 mL of solvent(containing 0.1 mL of Tween 80 and 0.1 mL of absolute ethanol)was injected into the pericardium of rats in the vehicle group.The rats in the capsaicin group and LRN electrical damage+capsaicin group were injected with 0.2 mL capsaicin(0.01 g·L-1)into the pericardium,and rats in the LRN electrical damage group were not injected with any solution.While the drugs were injected into the pericardium,the number of electromyographic(EMG)response that exceeded the baseline activity by 10%of the rat′s dorsi trapezius muscle was recorded.The number of EMG response of rats in the blank group was recorded after maintaining anesthesia for 1 hour.After 30 minutes of intrapericardial injection of drugs,the rats in each group were perfused with fixative and T3-T5 spinal cords were taken.Immunohistochemical staining was used to detect the number of pCREB immunopositive cells in the spinal dorsal horn of rats in each group.Results The rats in the blank group,the vehicle group and the LRN electrical damage group did not have an EMG response that exceeded the baseline activity by 10%.The number of EMG response in the dorsi trapezius muscle and pCREB immunopositive cells in the spinal dorsal horn of rats in the capsaicin group and the LRN electrical damage+capsaicin group were significantly higher than those in the blank group,the vehicle group and the LRN electrical damage group(P<0.05).The number of EMG response in the dorsi trapezius muscle and pCREB immunopositive cells in the spinal dorsal horn of rats in the LRN electrical damage+capsaicin group were significantly higher than those in the capsaicin group(P<0.05).Conclusion Intrapericardial injection of capsaicin can induce the EMG response of the dorsal trapezius muscle and increase the number of pCREB immunopositive cells in the spinal dorsal horn of rats.LRN has a downward tension inhibition effect on rat′s heart nociception.
作者
韩曼
刘晓华
王少兰
杜剑青
HAN Man;LIU Xiaohua;WANG Shaolan;DU Jianqing(College of Medicine,Shaanxi University of Chinese Medicine,Xianyang 712046,Shaanxi Province,China;Department of Physiology and Pathophysiology,College of Medicine,Xi′an Jiaotong University,Xi′an 710061,Shaanxi Province,China)
出处
《新乡医学院学报》
CAS
2020年第12期1114-1117,共4页
Journal of Xinxiang Medical University
基金
国家自然科学基金资助项目(编号:31171068,81904038)
陕西中医药大学针药结合防治冠心病临床基础研究创新团队基金(编号:2019-YS06)。
关键词
辣椒素
磷酸化环磷酸腺苷反应元件结合蛋白
延髓外侧网状核
肌电
下行紧张性抑制
capsaicin
phosphorylated cyclic adenosine monophosphate response element binding protein
lateral reticular nucleus
electromyogram
downward tension inhibition
