缬草醛对肠易激综合征模型大鼠胃肠敏感性和结肠中5-HIAA及5-HT相关受体蛋白表达的影响作用

Influences of baldrinal on gastrointestinal sensitivity and expressions of 5-HIAA and relevant receptors of 5-HT in rats with irritable bowel syndrome

目的探讨蜘蛛香环烯醚萜类成分缬草醛对慢-急性应激致肠易激综合征(IBS)模型大鼠的治疗作用及其对5-羟吲哚乙酸(5-HIAA)及5-羟色胺(5-HT)相关受体蛋白表达的影响作用。方法将SD雄性大鼠平均随机分为空白对照组、模型组及缬草醛高、中、低剂量组(0.6、0.3、0.15 mg/kg)、匹维溴铵组(25 mg/kg)。采用慢-急性应激结合孤养的方法建立IBS大鼠模型,观察缬草醛对IBS模型大鼠腹部回撤反射(AWR)评分的影响作用;使用高效液相色谱法测定大鼠结肠中5-HIAA含量;使用Western Blot法检测缬草醛对IBS模型大鼠结肠5-HT1A、5-HT3A及5-HTR4受体蛋白表达的影响。结果与模型组相比,缬草醛各剂量组均能够降低IBS模型大鼠AWR评分,并降低结肠内5-HIAA含量(P<0.05);缬草醛各剂量组均可调节结肠内5-HT1A、5-HT3A及5-HTR4受体的蛋白表达。结论缬草醛对慢-急性应激致IBS模型大鼠的胃肠道功能亢进有明显抑制作用,可降低内脏敏感性,提示蜘蛛香环烯醚萜对IBS的症状有改善作用,作用机制可能与调节结肠内5-HIAA含量及5-HT相关受体的蛋白表达水平相关。

Objective To investigate the effect of baldrinal on irritable bowel syndrome （IBS） induced by chronic-acute stress and its influences on the protein expressions of 5-hydroxyindoleacetic acid （5-HIAA） and relevant receptors of 5-hydroxytryptamine （5-HT） in rats. Methods SD rats were randomly divided into control group, model group, high-dose baldrinal group （0.6 mg/kg）, mid-dose baldrinal group （0.3 mg/kg）, low-dose baldrinal group （0.15 mg/kg） and pinaverium group （25 mg/kg）. The rat model of IBS was established by using chronic-acute stress combined with independent feeding for observing the influence of baldrinal on the scores of abdominal withdraw reflection （AWR）. The content of colonic 5- HIAA was detected by using high performance liquid chromatography （ HPLC）, and influences of baldrinal on protein expressions of colonic 5-HT1A, 5-HT3A and 5-HTR4 were detected by using Western blotting.Results The scores of AWR content of colonic 5-HIAA were decreased in high-dose baldrinal group, middose baldrinal group and low - dose baldrinal group compared with model group （P 〈 0.05 ）. The protein expressions of colonic 5-HT1A, 5-HT3A and 5-HTR4 were regulated in high-dose baldrinal group, middose baldrinal group and low-dose baldrinal group. Conclusion Baldrinal has significant inhibitory effect on gastrointestinal hyperfunction in rat model of IBS and reduce viscera sensitivity, which indicates that baldrinal can relieve IBS symptoms. The effective mechanism may be related to the regulation effect of baldrinal on 5-HIAA contents and protein expressions of relevant receptors of 5-HT.