中文摘要：

目的：观察0.0250.200 Gy X线低剂量电离辐射后324 h小鼠生精细胞线粒体结构、睾丸组织内ATPase和生精细胞钙离子浓度的变化,阐明线粒体结构与相关生物学功能改变在调控凋亡中的作用。方法：透射电镜检测小鼠睾丸生精细胞线粒体结构的改变;蛋白酶法检测ATPase活性的改变;以Fluo-3为探针,流式细胞术检测钙离子浓度（[Ca^2＋]i）的变化。结果：0.075 Gy照射后12 h,小鼠精原细胞与精母细胞线粒体肿胀、空泡化、嵴断裂;精子细胞核固缩,顶体囊泡结构模糊,核膜结构不清楚,线粒体空泡化。0.0250.200 Gy照射后12 h,睾丸组织中Na^＋-K^＋-ATPase活性较0 Gy照射降低,其中0.0500.200 Gy较0 Gy显著降低（P〈0.05）,Ca^2＋-ATPase活性均较0 Gy照射显著降低（P〈0.05）;生精细胞中[Ca^2＋]i也具有同样的剂量-效应关系,其中0.075 Gy照射后,较0 Gy显著降低（P〈0.05）。0.075 Gy照射后324 h,睾丸组织中Na^＋-K^＋-ATPase活性较0 h均显著降低（P〈0.05）;Ca^2＋-ATPase活性在3 h稍有升高后,624 h较0 h均显著降低（P〈0.05）;生精细胞中[Ca^2＋]i也具有相似的时程-效应关系。结论：低剂量电离辐射能够诱导小鼠睾丸生精细胞线粒体结构的改变;同时,其诱导ATPase活性和[Ca^2＋]i的变化具有剂量-效应与时程-效应规律性。

英文摘要：

Objective To observe the ultrastructure,ATPase activity and Ca^2＋ concentration（i） of mitochondria in the sperematogenic cells of mouse testes 3-24 h after low dose radiation with 0.025-0.200 Gy X-rays,and illuminate the effects of mitochondrion structure and relative biological function on apoptosis.Methods The ultrastructure changes of mitochondria in the spermatogenic cells were observed with transmission electron microscope;the ATPase activity was measured with protein enzymic method;i was measured indirectly by flow cytometry with Fluo-3 probes.Results The mitochondria swelled and vacuolizated,and their cristae were broken in the spermatogonia and spermatocytes 12 h after irradiation,and their nuclei were karyopyknosis,the acrosomal vesicle structure was ambiguity,the membrane structure was unclear,and the mitochondria in spermatids were vacuolization.The activities of Na^＋-K^＋-ATPase in mouse testis tissue 12 h after irradiated with 0.025-0.200 Gy decreased compared with those with0 Gy,the Na＋-K＋-ATPase activities of the cells irradiated with 0.05-0.200 Gy decreased significantly compared with those with 0 Gy（P〈 0.05）,and Ca^2＋-ATPase of the cells irradiated with 0.025-0.200 Gy decreased significantly compared with those with 0 Gy（P〈 0.05）.The change of [Ca^2＋]i in mouse testis spermatogenic cells had similar dose-response relationship,[Ca^2＋]i after irradiated with 0.075 Gy decreased compared with those with 0 Gy（P〈 0.05）.After 0.075 Gy irradiation for 3-24 h,the activities of Na^＋-K^＋-ATPase in mouse testis tissues decreased obviously compared with those at 0 h（P〈 0.05）,the activities of Ca^2＋-ATPase in mouse testis tissues increased slightly at 3 h,then decreased at 6-24 h compared with those at 0 h（P〈 0.05）;i in mouse testis spermatogenic cells had similar time course-response relationship,i at 12 h decreased significantly compared with at 0 h（P〈 0.05）.Conclusion Low dose radiation could induce the structure changes in the spermatogenic cell