油菜籽粕生物碱对家兔离体回肠平滑肌收缩功能的影响及机制

Effect of rapeseed meal alkaloid on contractility of isolated ileum smooth muscle of rabbits

目的：观察油菜籽粕生物碱对家兔离体肠平滑肌收缩功能的影响。方法取禁食24 h家兔15只，槌击后枕部致死，迅速剖开腹腔，制备离体肠管，肠管上端接肌张力换能器，下端固定于金属钩上，调整肠管初负荷为2．0 g，蠕动平稳30 min。筛选13个舒缩频率、张力稳定的肠管，向13个麦氏浴槽中分别加入0、0．5、12、、4、6、8、10、20、40、60、80、100μg/μL油菜籽粕生物碱溶液，每个浓度的给药体积为5μL，以0μg/μL油菜籽粕生物碱作为空白对照，用MedLab生物信号采集处理系统软件记录并分析肠管的的蠕动曲线，用周期测量法测定给药后蠕动波的频率，用区间测量法测量给药后的张力。采用M受体阻断剂（阿托品）孵育肌条，观察油菜籽粕生物碱在M受体阻断剂存在下对兔肠管平滑肌收缩效应的变化。结果0、0．5、1、2、4、6、8、10、20、40、60、80、100μg/μL的油菜籽粕生物碱对家兔离体肠平滑肌的收缩频率均无明显影响。6～60μg/μL油菜籽粕生物碱作用后兔离体肠管的张力明显提高，与空白对照组相比，P＜0．05；油菜籽粕生物碱浓度在0．5～40μg/μL范围内对家兔离体肠平滑肌收缩作用具有一定的量效关系；M受体阻断剂阿托品对油菜籽粕生物碱引起的肌条收缩有抑制作用，但抑制作用不完全。结论油菜籽粕生物碱对家兔离体肠管平滑肌具有兴奋作用，其兴奋肠管的作用与激动M受体有关。

Abtsract：Objective To observe the effect of rapeseed meal alkaloid on the contractility of isolated ileum smooth muscle of rabbits .Methods Fifteen fasted twenty four hours rabits executed by knock on the head , slited abdomen quickly and separated isolated ileum smooth muscle , the top of isolated ileum smooth muscle connected with tonotransducer and the bottom fasten on the metal hook , adjust the load at2.0 g, steady peristalsis in 30 min.To filtrate thirteen steady frequency and tension ileum in thirteen bath , add rapeseed meal alkaloid 0、0.5、1、2、4、6、8、10、20、40、60、80、100μg/μL with them separately ,each dose volume is 5μL, 0μg/μL rapeseed meal alkaloid as the blank control , recorded and analyzed peristal-tic waves with Medlab -U/4C501H biological function experimental system , measured after treated frequency by cycle measurement and after treated tension by interval measurement .The muscle strips were incubated with M receptor blocker （atropine）to observe the effects of rapeseed meal alkaloid contractile activity in the presence of atropine .Results 0、0.5、1、2、4、6、8、10、20、40、60、80、100 μg/μL rapeseed meal alkaloid had no obvious effect on the contraction frequency of isola -ted ileum smooth muscle strips .The 6-60μg/μL of rapeseed meal alkaloid compared with the blank control can obviously increase the tension of muscle strips（P〈0.05）, the contractile activity increased with the dose （from 0.5 μg/μL to 40μg/μL）.M receptor blocker（atropine） can inhibit the contraction effect caused by rapeseed meal alkaloid but the effect is incomplete .Conclusions Rapeseed meal alkaloi has excitatory effect on the contraction effect of isolated ileum smooth mus -cle and the effect was related with the M receptor excitement .