野鸢尾苷的制备及其对小鼠离体小肠平滑肌调节作用研究

Preparation of iridin and its regulatory effect on isolated mouse intestinal smooth muscle

目的:从中药川射干中分离制备野鸢尾苷单体,初步探究野鸢尾苷对小鼠离体小肠平滑肌调节作用。方法:采用多溶剂萃取法制备野鸢尾苷,采用改良的Ellman比色法探究野鸢尾苷对乙酰胆碱酯酶(AChE)活性的影响;并结合采用离体小肠平滑肌实验方法,取小鼠小肠平滑肌,在K⁃H液中制备小肠平滑肌环,通过BL⁃420S生物机能实验系统测定其张力的变化,观察野鸢尾苷对小鼠离体小肠平滑肌静息张力及对新斯的明、碘解磷定诱导小肠平滑肌收缩的影响。结果:多溶剂萃取法所得的野鸢尾苷单体,经HPLC峰面积归一化法计算其纯度>98%;野鸢尾苷对AChE活性具有抑制作用,其IC_(50)为4.09 mg·mL^(-1),且呈剂量依赖关系;野鸢尾苷(0.014~4.604 mg·mL^(-1))对正常小鼠离体小肠收缩有明显的兴奋作用,且抑制作用呈剂量依赖性,野鸢尾苷对胆碱酯酶复活剂碘解磷定引起小肠收缩抑制有显著性的拮抗作用(P<0.05),对胆碱酯酶抑制剂新斯的明促进小肠运动没有显著性协同作用(P>0.05)。结论:多溶剂萃取法是一种简单、高效的分离制备川射干中野鸢尾苷的方法;野鸢尾苷具有抑制AChE的拟胆碱作用,可促进小肠收缩运动,有望成为AChE抑制剂的候选物。

Objective:To isolate and prepare iridin monomer from traditional Chinese medicine Iridis tectori Rhizoma,and to explore the regulatory effect of iridin on the isolated intestinal muscle in vitro.Methods:The multi⁃solvent extraction method was used to prepare Iridin.The effect of iridin on acetylcholinesterase(AChE)activity was studied by modified Ellman colorimetry.The isolated intestinal muscle experiment was used for in vitro evaluation.In this study,the mouse small intestinal smooth muscle was obtained,from which the small intestinal smooth muscle ring was prepared in K⁃H solution.The change of the tension was measured by the BL⁃420S biological function experimental system.The resting tension and its effects on the contraction of small intestinal smooth muscle induced by neostigmine and pralidoxime iodide were investigated.Results:The iridin monomer obtained by the multi⁃solvent extraction method has a purity of over 98%calculated by the HPLC peak area normalization method.Iridin had inhibitory effect on AChE activity with a dose⁃dependent manner,and its half⁃inhibitory concentration(IC_(50))is 4.09 mg·mL^(-1).Iridin(0.014~4.604 mg·mL^(-1))had obvious excitatory effect on the contraction of isolated small intestine in normal mice,and the inhibitory effect was dose⁃dependent.Iridin had a significant antagonistic effect on the inhibition of small intestinal contraction caused by the cholinesterase revitalizer iodopyridine(P<0.05),but had no significant synergistic effect on promoting the small intestinal motility by the cholinesterase inhibitor neostigmine(P>0.05).Conclusion:Multi⁃solvent extraction method is a simple and efficient method for the isolation and preparation of iridin in Iridis tectori Rhizoma,and iridin has the cholinergic effect on inhibiting AChE.It can promote the contraction of the small intestine,and is expected to be a candidate for ache inhibitor.