小鼠雄性生殖细胞生后发育中的程序性死亡

为了观察小鼠睾丸生后发育过程中生殖细胞自发死亡的方式与规律。用生后０、１、４、７、１０、１３、１８和５０ｄＡ／Ｊ系不鼠，一侧睾丸用２．５％戊二醛，另一侧睾丸用４％多聚甲醛固定１８ｈ后，分别用树脂或石蜡包埋，年鉴备超薄和连续石蜡切片，进行电镜观察和ＴＵＮＥＬ染色光镜观察。电镜观察显示，在出生当日，可见个别呈死特征的变性生殖细胞，核质溶解，但无染色质聚集。核周间隙扩大，线粒体和内质网等细胞器肿胀，有空

PROGRAMMED CELL DEATH OF MALE GERM CELLS OF MOUSE DURING POSTNATAL DEVELOPMENT

Observing the occurrence and time pattern of the autonomous death of the male germ cells of mouse during postnatal development. A/J mice of 0,1,4,7,10,13,18 and 50 day old were used. One testis of each mouse was fixed with 2 5% glutaraldehyde, another was fixed with 4% paraformaldehyde for 18 h, and then processed for resin and paraffin embedding, respectively. Ultrathin and paraffin sections were made and subjected to EM observation and TUNEL (terminal deoxy UTP nick end labeling) staining. It was shown by EM that in the day of birth (0 day), degenerated germ cells of necrotic nature could be seen with lysis of the nuclei, but without aggregation of chromatin. The perinuclear cisternae extended, the mitochondria and endoplasmic reticulums swollen, and vacuoles could be found in the cytoplasm. The cell membrane has processes and bubbles. In the 1 day old mouse testes, death cells were hardly seen. Death germ cells of typical apoptotic nature were initially found in 4 day old testes, their numbers increased as the mice grew, and were most frequently found in the testes of 10 13 day old mice. TUNEL staining also showed similar results with the EM. TUNEL positive cells were also first found in 4 day after birth, their numbers reached peak in 10 13 day after birth, then gradually decreased. The autonomous death of male germ cells of mouse during postnatal development mainly occurs by the way of apoptosis, but in certain stages of development, they appear in the nature of necrosis. The occurrence of apoptosis showed a close relationship with the mitotic activities of the germ cells.