尿激酶型纤溶酶原激活因子对小鼠获能精子线粒体膜电位的影响

Effect of Urokinase-Type Plasminogen Activator on the Mitochondrial Membrane Potential of Mouse Capaciated-Spermatozoa in vitro

目的:检测尿激酶型纤溶酶原激活因子(uPA)体外对小鼠获能精子线粒体膜电位的影响。方法:采用线粒体膜电位荧光染料JC-1,利用流式细胞仪和荧光显微镜检测分别与uPA(实验组)和BWW液(对照组)共孵育0、5、15、30、60min的小鼠获能精子线粒体膜电位状态。结果:①在uPA作用第5、15min时,精子体内平均荧光强度较作用前显著增加,高膜电位的精子数量百分率相应增加(P<0.05)。②与对照组相比,实验组在uPA作用5、15min时的高膜电位精子数量百分率,以及作用15、30、60min时的精子线粒体膜电位平均荧光强度显著增加(P<0.05)。结论:uPA在体外可以增加小鼠获能精子的线粒体膜电位,并使高膜电位状态维持一段时间,为获能精子提供充足的能量供应。

Objective ： To study the mechanism of uPA improving sperm capacitation by investigating the effect of uPA on the mitochondrial function of mouse capacitated-sperm in vitro. Methods ： Mitochondrial function of mouse capacitated-spermatozoa was evaluated through the assessment of mitochondrial membrane potential using JC-1 performed by flow cytometer and fluorescent microscope respectively. The experiment and the control groups were designed according to the presence or absence of uPA, each divided into 5 subgroups based on the different time of uPA treatment （or BWW in the control groups） at 0, 5, 15, 30 and 60 min respectively. Resuits： ①Compared with that at 0 min, the mean fluorescence intensity of JC-1 within the spermatozoal body and the percentage of orange-red colored spermatozoa in the experiment group were increased significantly at 5 and 15 min respectively after uPA incubation （P 〈 0.05 ）. ②The mean fluorescence intensity of JC-1 within the spermatozoal body at 15,30 and 60 min and the percentage of orange-red colored spermatozoa at 5 and 15 min in the group were significantly higher than those in the control group （ P 〈 0.05 ）. Conclusion： uPA could increase the mitochondrial membrane potential of mouse capacitated-spermatozoa in vitro, and maintain it at a high level for a certain period of time. By enhancing sperm mitochondrial function, uPA may provide sufficient energy for capacitatedspermatozoa to increase their motility and change their motor pattern, which might be one of the therapeutic mechanisms of uPA on male infertility.