摘要
目的:研究地骨皮提取物(CLE)对α-葡萄糖苷酶的抑制作用,并对其降血糖的作用机制进行探讨。方法:提取大鼠小肠中α-葡萄糖苷酶,采用葡萄糖试剂盒测定酶活力;通过体外抑制实验和离体器官实验测定反应体系中葡萄糖浓度和淀粉光密度值,分别计算药物对蔗糖酶和淀粉酶的抑制率;以底物浓度的倒数作为横坐标,以反映速率的倒数作为纵坐标,双倒数作图判断CLE对α-葡萄糖苷酶抑制作用类型。结果:大鼠小肠酶活力值为77.4个活力单位;与正常对照比较,CLE低、中、高剂量组对蔗糖酶的抑制率明显增加(P<0.05,P<0.05,P<0.01);与正常对照比较,CLE低、中、高剂量组对淀粉酶抑制率明显增加(P<0.01,P<0.01,P<0.01);抑制曲线实验表明,最大反应速度随CLE浓度的变化而变化,但米氏常数Km不变。结论:CLE对α-葡萄糖苷酶具有良好的抑制作用。
Objective： To study the inhibitory effect of Cortex Lycii extract （CLE） on alpha-gluco- sidase by pharmacodynamie experiments in vitro, and to discuss the mechanism of its hypoglycemic activi- ty. Methods：The alpha-glucosidase was extracted form the small intestine of rats, and the activity of a- glucosidase was determined by glucose kit. The concentration of glucose and the optical density value of starch in the reaction system were determined by the inhibitory experiment in vitro and the in vivo experiment, and the inhibitory rate of drug were detected respectively. The reciprocal of concentration of sub- strate was used as abscissa, and the reciprocal of reaction rate as ordinate, the Lineweaver-Burk plot was applied to determine the type of inhibited alpha-glucosidase activity. Results： The activity of a-glucosidase in rat small intestine was 77.4μmol - L-1min-1. The low, moderate, high dose CLE inhibited the activi- ty of alpha-glucosidase comparing with normal control group （P〈0.05, P〈0.05, P〈：0.01）, and they al- so inhibited the hydrolytic effect of amylase （P〈0.01, P〈0.01, P〈0.01）. The inhibitory curve experi- ment showed that the maximum reaction rate changed as concentration of CLE changed, but Michaelis constant（Km） remained the same. Conclusion： CLE has superior inhibition on a-glucosidase.
出处
《海南医学院学报》
CAS
2012年第10期1379-1381,1387,共4页
Journal of Hainan Medical University
基金
中国高校医学期刊临床专项资金项目(112210339)~~
