Zayed A E, Hifny A, Abou-Elmagd A, Wrobel K H
Institute of Anatomy, University of Regensburg, Germany.
Ann Anat. 1995 May;177(3):199-212. doi: 10.1016/S0940-9602(11)80185-8.
The morphology and morphometry of camel testicular intertubular tissue are reported for different seasons of the year. The intertubular tissue occupies a comparatively large portion of the camel testis ranging from about 24% in autumn to about 39% in spring. The volume percentages of the different intertubular tissue constituents, namely Leydig cells, blood vessels, lymph vessels and various connective tissue components, also display clear seasonal changes. Early in winter, the intertubular tissue is richly vascularized by blood vessels (about 18% of the intertubular volume), whereas lymph vessels constitute only about 3%. This remarkable abundance of blood vessels coincides with the presence of voluminous and active Leydig cells that represent about 44% of the total. In spring, an immense expansion of the lymph vessels is observed (up to about 10% of intertubular tissue), but no change is seen in blood vessels. The Leydig cells in this season constitute only about 19% of the total. In summer, the vascular compartment occupies nearly the same volume as in early winter but with fewer blood and more lymph vessels. The Leydig cell volume percentage is markedly increased (39.3%) as compared with spring. In autumn, blood and lymph vessels record their lowest volume percentages (12% and 2.5%, respectively) and Leydig cell volume is also decreased as compared to summer. The Leydig cell morphology evidently points to two periods of elevated activity during the year. The first period occurs early in winter and is characterised by voluminous Leydig cells (average volume: 1614 microns3) with a well developed and highly organised SER. By spring, the cells are reduced in size (926 microns3) due to a decrease in the amount of SER. The second period of elevated Leydig cell activity is observed in summer and is again characterised by an increased cell volume (1420 microns3) as a consequence of SER development. In summer, however, the SER is not as highly organised as in early winter. The absolute number of Leydig cells per testis also shows clear changes from season to season, being lowest in autumn (3.68 x 10(9) cells) and highest in late winter and spring (6.04 x 10(9) cells). Thus, camel Leydig cells are subject to a permanent turnover. Degenerating Leydig cells are replaced the year round by undifferentiated fibroblastic precursors, whereas Leydig cell mitoses are a rare observation. The strongest waves of replacement seem to follow the peaks of increased Leydig cell activity and occur between summer and autumn as well as in late winter and spring.
本文报道了一年中不同季节骆驼睾丸间质组织的形态学和形态计量学特征。间质组织在骆驼睾丸中所占比例相对较大，从秋季的约24%到春季的约39%不等。不同间质组织成分，即睾丸间质细胞、血管、淋巴管和各种结缔组织成分的体积百分比也呈现出明显的季节性变化。初冬时，间质组织血管丰富（约占间质体积的18%），而淋巴管仅占约3%。这种显著丰富的血管与大量活跃的睾丸间质细胞同时存在，这些细胞约占总数的44%。在春季，观察到淋巴管大量扩张（高达间质组织的约10%），但血管未见变化。这个季节的睾丸间质细胞仅占总数的约19%。在夏季，血管部分的体积与初冬时几乎相同，但血管较少，淋巴管较多。与春季相比，睾丸间质细胞体积百分比显著增加（39.3%）。在秋季，血管和淋巴管的体积百分比达到最低（分别为12%和2.5%），与夏季相比，睾丸间质细胞体积也有所减少。睾丸间质细胞的形态明显表明一年中有两个活动增强期。第一个时期发生在初冬，其特征是睾丸间质细胞体积大（平均体积：1614立方微米），滑面内质网发达且高度有序。到春季，由于滑面内质网数量减少，细胞体积减小（926立方微米）。第二个睾丸间质细胞活动增强期出现在夏季，其特征同样是由于滑面内质网的发育，细胞体积增大（1420立方微米）。然而，在夏季，滑面内质网的有序程度不如初冬时高。每个睾丸中睾丸间质细胞的绝对数量也呈现出明显的季节性变化，秋季最低（3.68×10⁹个细胞），冬末和春季最高（6.04×10⁹个细胞）。因此，骆驼的睾丸间质细胞处于持续更新状态。退化的睾丸间质细胞全年都被未分化的成纤维细胞前体所取代，而睾丸间质细胞的有丝分裂则很少见。最强的替代浪潮似乎跟随睾丸间质细胞活动增加的峰值，发生在夏季和秋季之间以及冬末和春季。
