Abstract：
Our research aimed to provide complete histological, histochemical and ultrastructural features of the lacrimal gland of the one-humped camel (Camelus dromedarius) as well as novel insights into its adaptability to the Egyptian desert. Our study was applied to 20 fresh lacrimal glands collected from 10 camels instantly after their slaughtering. The results revealed that the gland was a compound tubulo-acinar gland, and its acini were enclosed by a thick connective tissue capsule that was very rich in elastic and collagen fibres. The gland acini had irregular lumens and were composed of conical to pyramidal cells. The nuclei of secretory cells were found in the basal part, and the cytoplasm was eosinophilic and granular. The glandular tissue consisted of serous and mucous acini and seromucous secretory cells. Histochemically, there was a significant amount of neutral mucopolysaccharides in the acini in which mucous cells had a significant periodic acid-Schiff (PAS)-positive reaction, whereas seromucous cells had a mild PAS-positive reaction. Ultrastructurally, the lacrimal cells had numerous secretory vesicles with contents of moderately to highly electron-dense cytoplasm. The nuclear envelope consisted of two prominent membranes surrounding the peri-nuclear cisterna. The acinar cells had numerous electron-lucent and moderately electron-dense secretory granules, mainly situated on the apical surface, and secreted their contents into the lumen. The luminal surface of the mucous secretory cells represents the remains of secretory granules discharged by the merocrine mechanism. In conclusion, the mucous secretion is believed to aid in the washing and moistening of the eyeball, particularly in dry, hot and dusty environments.
摘要：
我们的研究旨在提供完整的组织学，单峰骆驼（Camelusdromedarius）泪腺的组织化学和超微结构特征，以及对其对埃及沙漠的适应性的新颖见解。我们的研究适用于屠宰后立即从10头骆驼中收集的20个新鲜泪腺。结果表明，腺体是一个复合的肾小管-腺泡腺，它的腺泡被一层厚厚的结缔组织包膜包裹着，里面富含弹性和胶原纤维。腺泡有不规则的管腔，由圆锥形到锥体细胞组成。在基底部分发现了分泌细胞的细胞核，细胞质呈嗜酸性和颗粒状。腺体组织由浆液和粘液腺泡和浆液分泌细胞组成。组织化学，腺泡中存在大量的中性粘多糖，其中粘液细胞具有明显的高碘酸希夫（PAS）阳性反应，而浆膜细胞有轻度的PAS阳性反应。超微结构，泪腺细胞有许多分泌囊泡，其内容物具有中等至高度电子致密的细胞质。核被膜由围绕核周水箱的两个突出的膜组成。腺泡细胞有许多电子透明和中等电子密集的分泌颗粒，主要位于顶端表面，并将它们的内容物分泌到管腔中。粘液分泌细胞的腔表面代表了通过merocrine机制排出的分泌颗粒的残留物。总之,粘液分泌物被认为有助于清洗和润湿眼球，特别是在干燥，炎热和尘土飞扬的环境。
