电针下调内脏高敏感性大鼠结肠NGF和NGFR的表达

摘要

目的：观察电针对内脏高敏感大鼠结肠神经生长因子(nerve growth factor, NGF)和神经生长因子受体(nerve growth factor receptor, NGFR)表达的影响，探讨电针治疗慢性内脏高敏感性的作用机制。方法：将24只新生乳鼠随机分为正常组、模型组和电针组。参照 Al-Chaer 法制备内脏高敏感性大鼠模型。电针组予电针天枢、上巨虚治疗，每次20分钟，每天1次，连续7天。首次治疗后，通过观察大鼠腹壁撤回反射(abdominal withdrawal reflex, AWR)评分以评价内脏高敏感性大鼠的痛阈。治疗7天后，采集大鼠结肠组织进行NGF和NGFR免疫组织化学检测。结果：模型组大鼠的AWR评分均高于正常组，经电针治疗后均降低。模型组大鼠的结肠NGF和NGFR阳性表达较正常组显著增加(P＜0.05)，电针组治疗后NGF和NGFR阳性表达均显著降低(P＜0.001)。结论：电针可使内脏高敏感性大鼠的痛阈升高，并降低结肠的NGF和NGFR表达。电针对结肠NGF和NGFR表达的调节可能是其治疗慢性内脏高敏感性的外周作用机制之一。%Objective:To observe the effect of electroacupuncture (EA) on the expressions of colonic nerve growth factor (NGF) and nerve growth factor receptor (NGFR) in visceral hypersensitivity rats, and investigate the mechanisms of EA on chronic visceral hypersensitivity. n Methods:A total of 24 neonatal rats were randomly divided into a normal group, a model group and an EA group. The models of visceral hypersensitivity rats were prepared according to the method of Al-Chaer. The rats in the EA group were treated with EA at T ianshu (ST 25) and Shangjuxu (ST 37), 20 min for each time, once a day, for 7 consecutive days. After the first treatment, the observation of abdominal withdrawal reflex (AWR) was used to evaluate the pain threshold of visceral hypersensitivity rats. After 7-day treatments, the colonic tissue of rat was collected to test the immunohistochemistry of NGF and NGFR. n Results:The score of AWR in the model group was higher than that in the normal group, but the score decreased after EA treatment. The positive expressions of colonic NGF and NGFR in the model group were increased than those in the normal group (P<0.05), while they were both decreased in the EA group after treatment (P<0.001). n Conclusion:The EA could up-regulate the pain threshold of visceral hypersensitivity rats, and down-regulate the expressions of colonic NGF and NGFR. The regulation of the expressions of colonic NGF and NGFR would be one of the peripheral mechanisms of EA in treating chronic visceral hypersensitivity.