In order to evaluate the influence of reproductive activity on the functional role of the epididymal epithelium in the Egyptian dromedary camel, Connexin-43 (Cx-43), vascular endothelial growth factor (VEGF), and androgen receptor (AR) immunoreactivity in the epididymal epithelium and the fine structure of the principal, dark, basal, apical, and halo cells were investigated. The secretory activity of the principal cells was amplified in the breeding season, while its endocytotic function became more active in the nonbreeding season. This was evidenced by punctate strong immunoreactive signals for Cx-43, which appeared to be more intense in the apical region of these epithelial cells, and the extremely long slender stereocilia (microvilli) with multiple junctional complexes. The nonbreeding principal cells revealed granular immunoreactive signals for VEGF scattered in the apical and basal cytoplasm. Ultrastructurally, both extreme vacuolation and several multivesicular inclusion bodies were observed in their cytoplasm. Dark cell size greatly diminished in the nonbreeding season and their nuclear morphology greatly changed from oval to lobulated shape. The plasma membrane of the apical cells expressed several infoldings (microvilli) in the breeding season. However, it was almost smooth in the nonbreeding season except for a small microvillus that appeared as a bleb-like projection. In some regions, a strong dense immunoreactivity for VEGF could be recognized in the cytoplasm of the apical cells and some basal ones. Halo cells with numerous multivesicular inclusions occupying most of the cytoplasm and a lobulated eccentric nucleus were detected in the nonbreeding season. In conclusion, these findings indicate that the reproductive activity has a significant impact on the immunohistochemical and ultrastructural profiles of the epithelial cells lining the Egyptian dromedary camel epididymis.

中文翻译：

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骆驼附睾上皮细胞季节性变化的免疫组化和超微结构特征

为了评估生殖活动对埃及单峰骆驼附睾上皮功能作用的影响，连接蛋白 43 (Cx-43)、血管内皮生长因子 (VEGF) 和雄激素受体 (AR) 在附睾中的免疫反应性研究了上皮和主要细胞、暗细胞、基底细胞、顶端细胞和晕细胞的精细结构。主细胞的分泌活性在繁殖季节增强，而其内吞功能在非繁殖季节变得更加活跃。Cx-43 的点状强免疫反应信号证明了这一点，这些信号在这些上皮细胞的顶端区域似乎更强烈，以及具有多个连接复合物的极长纤细的静纤毛（微绒毛）。非繁殖主细胞显示分散在顶端和基底细胞质中的 VEGF 颗粒免疫反应信号。超微结构上，在它们的细胞质中观察到极端的空泡化和几个多泡包涵体。在非繁殖季节，暗细胞大小大大减小，其核形态从椭圆形变为分叶状。顶端细胞的质膜在繁殖季节表达了几个内折叠（微绒毛）。然而，在非繁殖季节它几乎是平稳的，除了一个小微绒毛，它看起来像一个气泡状的突起。在某些区域，可以在顶端细胞和一些基底细胞的细胞质中识别出对VEGF的强烈密集免疫反应。在非繁殖季节检测到具有占据大部分细胞质的大量多泡包涵体和分叶状偏心核的晕细胞。总之，这些发现表明，生殖活动对埃及单峰骆驼附睾上皮细胞的免疫组织化学和超微结构特征有显着影响。