Apoptosis and mitosis in gonocytes of the rat testis during foetal and neonatal development
Apoptosis and mitosis in gonocytes of the rat testis during foetal and neonatal development
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DOI：
10.1046/j.1365-2605.1999.00191.x
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发表时间：
1999-12-01
影响因子：
--
通讯作者：
Habert, R
中科院分区：
文献类型：
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作者：
Boulogne, B;Olaso, R;Habert, R
本研究旨在确定从胎龄14.5天到出生后9-10天大鼠整个发育过程中各种睾丸细胞类型的凋亡和有丝分裂程度。采用原位DNA断裂法（TUNEL法）检测细胞凋亡活性。在生殖细胞中检测到TUNEL阳性反应，而其他睾丸细胞均未标记。TUNEL阳性生殖细胞的形态是凋亡细胞的特征，与实验诱导的坏死中观察到的形态不同。染色的生殖细胞百分比在受孕后第15.5-16.5天（dpc）达到峰值，此后下降，从胎儿第18.5天起未发现TUNEL阳性生殖细胞。在出生后第2天，细胞凋亡恢复并增加，在第7天达到最大值。有丝分裂的生殖细胞，5-溴-2 '-脱氧尿苷（BrdU）掺入的免疫检测，是目前在相同的发展时期，但BrdU阳性/TUNEL阳性的生殖细胞的比例是在胎儿期比在新生儿期大得多。在器官型培养系统中，培养两天后，18.5天和20.5天胎儿睾丸外植体或3天新生儿睾丸外植体中生殖细胞的凋亡和有丝分裂活性的变化与体外观察到的相似。添加LH或FSH不影响生殖细胞的凋亡或有丝分裂。这些结果表明，生殖细胞的凋亡和有丝分裂都不依赖于促性腺激素，而主要受睾丸内因素的控制。
This study was undertaken to determine the extent of apoptosis and mitosis in the Various testicular cell types throughout rat development from foetal day 14.5 to postnatal days 9-10. Apoptotic activity was studied by detecting DNA fragmentation (TUNEL method) in situ. A TUNEL-positive reaction was detected in gonocytes, while none of the other testicular cells were labelled. The morphology of the TUNEL-positive gonocytes was characteristic of apoptotic cells and was different from that observed in experimentally induced necrosis. The percentage of stained gonocytes peaked on day 15.5-16.5 post-conception (dpc), decreased thereafter and no TUNEL-positive gonocytes were found from foetal day 18.5 onwards. On postnatal day 2, apoptosis resumed and increased to reach a maximum on day 7. Mitosis in the gonocyces, as evaluated by the immunodetection of 5-bromo-2'-deoxyuridine (BrdU) incorporation, was present during the same developmental periods but the ratio of BrdU-positive/ TUNEL-positive gonocytes was much greater in the foetal period than in the neonatal period. In an organotypic culture system, the changes in the apoptotic and mitotic activities of the gonocytes in testicular explants from foetuses on days 18.5 and 20.5 or from neonates on day 3, cultured for two days were similar to those observed in vitro. Addition of LH or FSH did not influence either apoptosis or mitosis in the germ cells. These results suggest that both apoptosis and mitosis of gonocytes are independent of gonadotrophins and are mainly controlled by intratesticular factors.