精索静脉曲张及精索静脉结扎术大鼠附睾组织中miR-210的表达及意义

Exoression and significance of miR-210 in the epididymis in rats with varicocele and following varicocelectomy

目的观察微小RNA 210（miR-210）在精索静脉曲张大鼠的附睾组织中的表达情况及精索静脉高位结扎术后改善情况，探讨精索静脉曲张高位结扎手术的意义。方法7周龄雄性SD大鼠21只，采用随机数字表法随机分为假手术组、曲张组和治疗组，每组7只。曲张组和治疗组大鼠建立精索静脉曲张模型；假手术组大鼠仅游离左肾静脉和左精索静脉与左髂总静脉间的交通支。术后8周，测量假手术组和曲张组大鼠的精索静脉直径，留取左侧附睾（甲醛固定，冻存备用）。治疗组大鼠行左精索静脉高位结扎术，4周后留取标本同假手术组和曲张组处理。将甲醛固定附睾组织进行HE染色，观察附睾损伤情况；反转录（RT）-PCR测定附睾组织miR-210的表达情况。每组最终获得5只大鼠标本。结果病理切片显示：曲张组与假手术组相比，附睾管内成熟精子数量减少、上皮分布不均匀，治疗组较曲张组明显改善；曲张组和治疗组结扎术前精索静脉直径比假手术组明显增粗（P〈0.01）。曲张组附睾组织中miR-210相对量（1.32±0.06）高于假手术组（0.98±0.14）（P〈0.01），治疗组（0.96±0.16）比曲张组相对含量减少（P〈0.01）；假手术组与治疗组相比变化不明显（P〉0.05）。结论精索静脉曲张导致附睾组织miR-210表达量增加；精索静脉曲张高位结扎可以修复附睾损伤，使附睾组织miR-210表达降低。

Objective To investigate the expression of microRNA 210 （miR-210） in the epididymis of rats with varicocele and changes in miR-210 expression following high spermatic vein ligation, so as to explore the significance of the surgery in treating varicocele. Methods A total of 21 male Sprague- Dawley （SD） rats aged 7 weeks were randomly divided into control group （n = 7 ）, experimental group （n = 7）, and surgical group （n = 7）. Varicocele model was established in both the experimental and surgical groups, while only vein isolation was performed in the control group. After 8 weeks, spermatic vein diameter were measured in the control and experimental rats, and collected the left epididymis （fixed in formaldehyde and frozen in refrigerator at -80 -C ）. In the surgical group, left high spermatic vein ligation was performed, and the left epididymis was collected after 4 weeks as in the control and the experimental groups. The fixed epididymis tissues were treated with HE staining for observation of tissue injuries. The miR-210 expression in the epididymis was detected with reverse transcription-polymerase chain reaction （RT-PCR）. At last every group had 5 rats. Results The pathological examination showed that the number and distribution of mature sperms in epididymal duct in the experimental group were lower and less even compared to the control group, while the two indicators in the surgical group were better than those in the experimental group. The diameter of the left spermatic vein in the experimental group and pre-treatment surgical group were significantly enlarged than in the control group （P 〈 0. 01 ）. The expression of miR-210 in the left epididymis in the experimental group was significantly higher compared with the control group （ 1.32 ±0. 06 vs 0. 98 ± 0. 14, P 〈 0. 01 ）, while the expression of miR-210 in the left epididymis in the surgical group was significantly decreased compared with the experimental group （0. 96 ±0. 16 vs 1.32 ±0. 06,P 〈 0. 01 ）; the difference between the control group and the surgical group was not statistically significant （P 〉 0. 05 ）. Conclusion The expression of miR-210 in the epididymis may be increased by varicocele and reduced after high ligation of the affected spermatic vein.