酒精染毒后大鼠睾丸生精小管超微结构的改变

目的:观察酒精染毒后大鼠睾丸生精小管超微结构的变化。方法:将48只W istar雄性性成熟健康大鼠随机分为对照组(A组)、染毒组(B组),每组24只,B组用50度酒精(6 m l/kg)每天灌胃染毒1次,连续39 d,A组用生理盐水灌胃(6 m l/kg);在第14、27、40 d分别从A、B两组中各处死8只大鼠,取睾丸组织,常规电镜制片,透射电镜观察大鼠睾丸生精小管超微结构。结果:透射电镜发现:对照组各时间段睾丸生精小管超微结构无明显变化,基膜平滑、致密、厚薄均匀,支持细胞胞质丰富、粗面内织网及线粒体较多,核大、核质均匀、核仁清楚,精原细胞与基膜和支持细胞之间连接紧密,紧密连接层次清楚。染毒组第1生精周期末(相当于第14 d)超微结构开始变化;第2、3个生精周期末(分别相当于第27、40 d)超微结构变化最明显,主要表现为:①支持细胞溶酶体增多,线粒体肿胀空泡化,细胞器模糊且数量减少,支持细胞内出现较大空泡,甚至支持细胞出现萎缩;②精原细胞与支持细胞及生精小管的基膜之间出现较多较大空泡;③精原细胞凋亡,凋亡小体边集;④生精小管内的精子有过多的胞质且有大小不一的空泡,尾部断面线粒体排列不整齐、缺失或堆积;⑤紧密连接层次改变、模糊不清;⑥基膜厚薄不均,基膜外胶原组织疏松增厚,成波浪式皱褶,可见基膜断裂。结论:酒精可引起大鼠睾丸生精小管的基膜、紧密连接、支持细胞等超微结构异常,并可引起精原细胞凋亡。

Ultrastructural Changes of the Rat Convoluted Seminiferous Tubule after Alcohol Consumption

OBJECTIVE: To study the ultrastructural changes of the rat convoluted seminiferous tubule after alcohol consumption. METHODS: Forty-eight Wistar mature male rats were divided into two groups randomly: control group (A) and experimental one (B). 6 ml/(kg x d) of 50 degrees alcohol was perfused through the gastric tube for 39 days in Group B; and 6 ml/(kg x d) of normal saline was supplemented in Group A. The ultrastructure of the rat convoluted seminiferous tubule was observed by transmission electron microscope at day 14, 27 and 40. RESULTS: In Group A, the pykno-basement membrane was unstriated and uniform, Sertoli cells showed cytoplasmic profusion, with big nucleus, well-distributed nucleoplasm, distinct nucleolus, more mitochondria and plain hierarchical tight-junction. And the ultrastructure of the rat convoluted seminiferous tubule in Group B began to change at the end of the first spermatogenic cycle (D 14) and changed more and more evidently with the ethanol administration, mainly as follows: (1) more lysosomes and vacuolisation found in Sertoli cells, and organelles decreased and blurry; (2) more and bigger vacuoles among the spermatogonia, Sertoli cells and basement membrane; (3) obvious apoptosis of spermatogonia and apoptotic bodies aggregated near the membrane; (4) more cytoplasm and vacuolisation in the sperm of the convoluted seminiferous tubule, and disarranged, deleted or clustered mitochondria in the sperm tail; (5) blurry and rigid tight-junction; (6) thickened, wrinkled or broken basement membrane and under-basement CONCLUSION: Alcohol can cause ultrastructural changes of the basement membrane, tight-junction and Sertoli cells of the membrane. rat convoluted seminiferous tubule and apoptosis of spermatogonia.