疏肝健脾法改善功能性胃肠病内脏敏感性及其机制的实验研究

Therapy of soothing liver and fortifying spleen for relieving visceral hypersensitivity in rats with functional gastrointestinal disorder and mechanism study

目的探讨疏肝健脾法对大鼠内脏敏感性的影响及其可能机制。方法母婴分离方法制作大鼠模型,将实验动物随机分为加味逍遥丸高、中、低剂量组,生理盐水组,模型空白组,正常对照组,雌雄各半;观察各组结肠球囊扩张(CRD)时腹部回缩反射(AWR)并评分。免疫组化法观察各组下丘脑促肾上腺皮质激素释放因子(CRF)、脊髓背角神经元c-fos、结肠5-HT3R的表达情况,采用ELISA方法检测血清中CRF含量。结果母婴分离法可使大鼠的内脏敏感性增高,雌鼠内脏敏感性更容易升高,直肠球囊扩张容量阈值明显减低(P<0.05)。加味逍遥丸组治疗前容量阈值差异无统计学意义,治疗后,容量阈值明显升高(P<0.05);治疗组下丘脑及血清CRF随着药物剂量的逐渐增加,含量逐渐减少,其中,高中剂量组,中低剂量组,差异有统计学意义(P<0.05)。脊髓c-fos、结肠5-HT3R的表达随着药物剂量的增加而逐渐减少,且有随剂量增加变化越明显的趋势(P<0.05)。结论新生期母婴分离法可使大鼠内脏敏感性增高,加味逍遥丸可降低大鼠的内脏敏感性,且有随剂量增加改善越明显的趋势,其可能的机制是通过减少下丘脑及外周CRF的分泌及释放以及抑制脊髓c-fos、结肠5-HT3R的表达,从而抑制脑肠轴兴奋,降低内脏敏感性。

Objective To investigate the influence of therapy of soothing liver and fortifying spleen on visceral hypersensitivity in rats and to study the mechanism. Methods The rat model was established with maternal separation （MS）. All rats were randomly divided into high-dose, mid-dose and low-dose Jiawei Xiaoyao Wan groups （high-dose group, mid-dose group and low-close group）, normal saline group （NS group）, model group and normal group （half male and half female）. The abdominal withdrawal reflex （AWR） was observed and graded during colorectal distension （CRD） in all groups. The expressions of corticotrophin-releasing factor （ CRF）, spinal cord dorsal horn neurons c-fos and colon 5-HTzR were observed by using immunohistochemistry technique, and content of serum CRF was detected by using enzyme-linked immunosorbent assay （ELISA）. Results MS improved the visceral hypersensitivity in rats especially in female rats, and reduced significantly the threshold of CRD （P 〈 0.05）. In Jiawei Xiaoyao Wan groups, the difference in the threshold of CRD was not statistically significant before treatment, and threshold of CRD increased significantly after treatment （ P 〈 0.05 ）. The content of CRF in hypothalamus and serum decreased as the dose of Jiawei Xiaoyao Wan increased in Jiawei Xiaoyao Wan groups, and the difference was statistically significant between high-dose group and mid-dose group or between mid-dose group and low-dose group （ P 〈 0.05 ）. @The expressions of spinal c-fos and colon 5-HT3R decreased as the dose of Jiawei Xiaoyao Wan increased showed a tendency of the expressions being more obvious as the increase of medicinal dose （ P 〈 0.05 ）. Conclusion MS can improve and Jiawei Xiaoyao Wan can decrease the visceral hypersensitivity, which has a tendency of the changes being more obvious as the increase of medicinal dose. The mechanism may be related to the inhibition of HPA axis and visceral sensitivity through reducing CRF secretion and release and inhibiting the expressions of spinal c-fos and colon 5-HT3R.