基于阳虚便秘模型的肉苁蓉通便作用的量效关系及机制研究

Mechanism and dosage-effect relationship of Cistanche on yang deficiency constipation model

目的观察肉苁蓉总提取物对阳虚便秘大鼠润肠通便作用的量效关系,探讨肉苁蓉润肠通便的作用机制。方法采用正常与阳虚便秘动物模型,对比考察肉苁蓉总提取物在1~4 g·kg^(-1)内对实验动物一般状态、排便功能、胃肠激素的影响,并统计分析肉苁蓉的量效关系及作用机制。结果肉苁蓉总提取物浓度为1 g·kg^(-1)有润肠通便作用,但与模型组相比差异无统计学意义(P>0.05),而中剂量组2 g·kg^(-1)肉苁蓉提取物能显著改善阳虚便秘大鼠的体征,增加体重,缩短首粒排便时间、增加6 h内排便量、增强结肠收缩功能,提高血清胃动素和血管活性肠肽水平,且与高剂量组4 g·kg^(-1)通便效果相当,与模型组相比差异有统计学意义(P<0.05)。在实验剂量内,通便效果似乎不再随剂量的加大而加强。结论肉苁蓉中、高剂量组通便效果相当,临床起效剂量为20 g·d^(-1),增加剂量不一定能增加通便的临床疗效;其作用机制可能与调节胃肠激素水平、增强肠道收缩力有关。

Objective To determine the dosage-effect relationship of Cistanche on yang deficiency constipationmodel, and discuss the laxation mechanism of Cistanche. Methods Normal and yang deficiency Constipation rat model were set up to determine the general status, defecation function, and gastrointestinal hormone at Cis- tanche dosage from 1 to 4 g · kg - 1. Statistical software was used to analyze the dose-effect relationship and mechanism of Cistanche. Results Laxative effect was shown when Cistanche extract was at 1 g · kg - 1 but had no significant difference compared with the model group （P 〉 0.05）. The middle dose （2 g·kg- 1） group had similar laxative effective with the high dose （4 g ·kg - 1） group but significantly improved the symptoms of yang deficiency constipation, increased weight, shortened the first defecation time, increased the amount of defecation within 6 h, promoted colonic motor function and increased the level of serum motilin and vasoactive intestinal peptide （P 〈 0.05）. The laxative effect seemed no longer strengthen with the dosage increase within the test doses. Conclusion There is no difference in laxative effect between the middle dose and the high dose of Cistanche extract. The clinical effective dose is 20 g per day, and the clinical effect dose not increase further with the dosage. The mechanism may be related to the regulation of gastrointestinal hormone levels.