芍药甙对家兔离体Oddi括约肌肌环收缩活动的影响

Effects of paeoniflorin on contractile activity of rabbit sphincter of Oddi muscle rings in vitro

[目的]了解芍药甙对家兔离体Oddi括约肌(sphincter of Oddi,SO)肌环收缩活动的影响。[方法]制备离体兔Oddi括约肌肌环标本,放置于平滑肌恒温灌流浴槽中,观察累积浓度芍药甙对乙酰胆碱(Ach)预收缩(乙酰胆碱组)的SO肌环的作用和芍药甙对经无钙液(无钙液组)、无钙液加肝素(肝素组)预处理的SO肌环的作用。[结果]当芍药甙浓度累积达(12.5、25、50、100)μmol/L时,对Ach(10-6mol/L)预收缩的SO肌环产生剂量依赖性舒张作用(P<0.05)。经无钙液预处理后,芍药甙(100μmol/L)对SO肌环的舒张作用未被阻断;但经无钙液加肝素预处理后,该作用被明显抑制。[结论]芍药甙对Oddi括约肌具有舒张作用。其机制可能与阻断平滑肌细胞内质网上的三磷酸肌醇敏感的钙离子通道,抑制内钙的释放有关。

[ Objective] To observe the effects of paeoniflorin （PA） on contractile activity of isolated rabbit sphincter of Oddi （SO） muscle rings. [ Methods] The organ-bath was used to observe the contractile activity of isolated smooth muscle from rabbit sphincter of Oddi muscle rings after cumulatively administrated different concentration of PA, the effect of accumulated PA on SO muscle rings in preconstricted with acetylcholine （Ach） was observed. The SO muscle rings were incubated with Ca^2 ＋ - free medium alone, or Ca^2 ＋ - free medium plus heparin before pre - contraction with Ach. [ Results ] When the concentration of PA was cumulated among 12.5,25,50 and 100 μmol/L,it caused concentration- dependent relaxation while SO muscle rings were pre-constricted with Ach （10^-6mol/L）. This effect was not inhibited by Ca^2＋ -free medium. However, the effect was attenuated by the co - incubation with heparin and Ca^2 ＋ - free medium [ without heparin ： （74.56±1.47） % vs （92.31±0.84） %, with heparin ： （ 95.98±0.52 ） % vs （ 95.03±0.43 ） % ]. [ Conclusion ] The results indicate that PA can relax the rabbit SO muscle rings in vitro. The mechanism may include the inhibition of intracellular calcium ions release by the 1,4,5 - triposphate inositol - receptor - dependent pathway in SO muscle ceils.