Vergouwen R P, Huiskamp R, Bas R J, Roepers-Gajadien H L, Davids J A, de Rooij D G
University of Utrecht, Department of Cell Biology, Medical School, The Netherlands.
Radiat Res. 1995 Jan;141(1):66-73.
The effects of prenatal X irradiation on postnatal development of the CBA/P mouse testis was studied. At days 14, 15 and 18 post coitus pregnant female mice were exposed to single doses of X rays ranging from 0.25-1.5 Gy. Higher doses resulted in extensive loss of fetal mice. In the male offspring, at days 3 and 31 post partum, the numbers of gonocytes, type A spermatogonia and Sertoli cells per testis were determined using the disector method. Furthermore, after irradiation at day 15 post coitus, the numbers of Leydig cells, mesenchymal cells, macrophages, myoid cells, lymphatic endothelial cells, endothelial cells and perivascular cells per testis were also determined at days 3 and 31 post partum. At day 3 post partum, the number of germ cells was decreased after irradiation at days 14 and 15 post coitus. A D0 value of 0.7 Gy was determined for the radiosensitivity of the gonocytes at day 14 post coitus. A D0 value of 0.8 Gy was determined for the gonocytes at day 15 post coitus which, however, seems to be less accurate. No accurate D0 value could be determined for the gonocytes at day 18 post coitus. At day 31 post partum, the repopulation of the seminiferous epithelium as well as testis weights and tubular diameters were more affected by irradiation with increasing age of the mice at the time of irradiation. The percentage of tubular cross sections showing spermatids decreased with increasing dose after irradiation at days 15 and 18 post coitus, but not after irradiation at day 14 post coitus. Furthermore, in tubular cross sections showing spermatids, exposure of testes to 1.25 and 1.5 Gy at day 18 post coitus resulted in significantly lower numbers of spermatids per cross section when compared to those testes exposed to the same doses at day 15 post coitus. This indicates that the radiosensitivity of the gonocytes increases with fetal age. Prenatal irradiation did not cause significant changes in the numbers per testis of the Sertoli cells or the interstitial cell types. The present results indicate that, in the fetal mouse testis, the spermatogonial stem cells are more sensitive to X irradiation than in the adult testis, while Sertoli cells and interstitial cells are relatively resistant.
研究了产前X射线照射对CBA/P小鼠睾丸出生后发育的影响。在交配后第14、15和18天，对怀孕的雌性小鼠进行单次X射线照射，剂量范围为0.25 - 1.5 Gy。较高剂量导致大量胎鼠死亡。对于雄性后代，在出生后第3天和31天，使用分割计数法确定每个睾丸中生殖母细胞、A型精原细胞和支持细胞的数量。此外，在交配后第15天进行照射后，在出生后第3天和31天还确定了每个睾丸中睾丸间质细胞、间充质细胞、巨噬细胞、肌样细胞、淋巴管内皮细胞、内皮细胞和血管周细胞的数量。在出生后第3天，交配后第14天和15天照射后生殖细胞数量减少。确定交配后第14天生殖母细胞的放射敏感性D0值为0.7 Gy。交配后第15天生殖母细胞的D0值为0.8 Gy，然而，这个值似乎不太准确。交配后第18天生殖母细胞无法确定准确的D0值。在出生后第31天，随着照射时小鼠年龄的增加，生精上皮的再增殖以及睾丸重量和管径受照射的影响更大。交配后第15天和18天照射后，显示精子细胞的管状横截面积百分比随剂量增加而降低，但交配后第14天照射后没有这种情况。此外，在显示精子细胞的管状横切面上，交配后第18天睾丸暴露于1.25和1.5 Gy时，每个横切面的精子细胞数量明显低于交配后第15天暴露于相同剂量的睾丸。这表明生殖母细胞的放射敏感性随胎龄增加。产前照射未导致每个睾丸中支持细胞或间质细胞类型数量的显著变化。目前的结果表明，在胎鼠睾丸中，精原干细胞对X射线照射比成年睾丸更敏感，而支持细胞和间质细胞相对抗性较强。
