短波辐射对大鼠睾丸组织细胞凋亡及氧化应激的影响研究

Effects of shortwave radiation on apoptosis and oxidative stress in testis tissue of rats

目的探讨短波辐射对大鼠睾丸组织细胞凋亡及氧化应激的影响。方法采用0 mW/cm^2、5 mW/cm^2、10 mW/cm^2和30 mW/cm^2短波辐射100只二级雄性Wistar大鼠6 min,并于辐射后1 d、7 d、14 d、28 d和3 m处死,采用TUNEL染色和定量分析技术检测大鼠睾丸组织生精细胞凋亡,采用黄嘌呤氧化镁法测定大鼠睾丸组织中超氧化物歧化酶(Superoxide Dismutase,SOD)活力,紫外分光法测定过氧化氢酶(Catalase,CAT)活力,硫代巴比妥酸法检测丙二醛(Malondialdehyde,MDA)水平,观察短波辐射对大鼠睾丸组织氧化应激的影响。结果与0 mW/cm^2组比较,5 mW/cm^2组大鼠于辐射后1天3个月,生精细胞细胞凋亡率,SOD、CAT活力和MDA含量均无明显改变;10 mW/cm^2组于辐射后1 d和7 d(P<0.05),30mW/cm^2组于辐射后1 d,7 d和14 d(P<0.01),生精细胞细胞凋亡率明显增加。大鼠睾丸组织SOD活力于10 mW/cm^2组辐射后7 d明显降低(P<0.01)、30 mW/cm^2组辐射后1 d,7 d和14 d明显降低(P<0.05或P<0.01)。大鼠睾丸组织CAT活力于10 mW/cm^2组辐射后1 d和7 d,30 mW/cm^2组辐射后1 d、7 d和14 d明显降低(P<0.01)。大鼠睾丸组织MDA含量于10 mW/cm^2组辐射后7 d,30 mW/cm^2组辐射后1 d和7 d明显升高(P<0.01)。结论 5 mW/cm^2短波辐射对大鼠睾丸组织生精细胞凋亡和SOD、CAT活力MDA含量未见显著影响;1030 mW/cm^2短波辐射可致大鼠睾丸组织生精细胞凋亡增加,SOD、CAT活力降低,MDA含量升高;且上述改变与辐射剂量呈正相关。

Objective To study the effect of shortwave radiation on the apoptosis and oxidative stress in testis tissue of rats. Methods 100 male Wistar rats were exposed to 0 mW/cm2,5 mW/cm2,10 mW/cm2 and 30 mW/cm2 short wave radiation,respectively,for six minutes. The rats were sacrificed at 1 d,7 d,14 d,28 d and 3 m after radiation. The apoptosis of the rats＇ spermatogenic cells was determined by TUNEL with quantitative analysis. The activity of superoxide dismutase（ SOD） in the testes of rats was determined by xanthine magnesia method,the activities of catalase（ CAT） were determined by ultraviolet spectrophotometry,and the level of Malondialdehyde（ MDA） were measured by thiobarbituric acid method.These measures were used to quantify the oxidative stress in testis tissue of rats exposed to short wave radiation. Results Compared with the group of 0 mW/cm2 exposure,the rats in the group of 5 mW/cm2 exposure showed no significant difference in the apoptotic rate of spermatogenic cells,SOD and CAT activities,and MDA content from the 1 d to 3 m after irradiation. However,the apoptotic rate of spermatogenic cells of rats in the group of 10 mW/cm2 exposure was significantly increased at 1 d and 7 d after irradiation（ P〈0. 05）,so was that of the rats in the group of 30 mW/cm2 exposure at 1 d,7 d and 14 d after irradiation（ P〈0. 01）. The activity of SOD in the testis tissue of rats in the group of 10 mW/cm2 exposure significantly decreased at 7 d after irradiation（ P〈0. 01）. Similarly,the SOD activity in the group of 30 mW/cm2 exposure also declined at 1 d,7 d and 14 d after irradiation（ P〈0. 05 or P〈0. 01）. In the group of 10 mW/cm2 exposure,the activity of CAT in the rat testis tissue decreased significantly at 1 d and 7 d after irradiation,while the group of 30 mW/cm2 exposure were also observed with a significant decrease in CAT activity at 1 d,7 d and 14 d after irradiation（ P〈0. 01）. The MDA content in testis tissue increased dramatically at 7 d after irradiation in the group of 10 mW/cm2 exposure,and such increase was also seen at 1 d and 7 d after irradiation in the group of 30 mW/cm2 exposure（ P〈0. 01）. Conclusion The shortwave radiation of 5 mW/cm2 had no significant effect on the apoptosis of spermatogenic cells and the activity of SOD and CAT in testis tissue of rat; 10 ~ 30 mW/cm2 shortwave radiation could increase the apoptosis of spermatogenic cells,reduce the SOD and CAT activities,and increase the MDA content. These changes were positively correlated to radiation dose.