Skin Physiology Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
Zoology Section, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
J Morphol. 2023 Aug;284(8):e21615. doi: 10.1002/jmor.21615.
In the present study, the epidermis of the hill stream fish Hara hara has been investigated employing scanning electron microscope, histology, histochemistry and immunofluorescence techniques. The epidermis is characteristically differentiated into plaques separated from each other by deep furrows. In plaques, the epidermis is keratinized. In contrast, in furrows, it is mucogenic. Surface epithelial cells in plaques get modified into characteristic spine-like unculi. At the distal ends of these unculi, we find tree-like branched dendritic structures. The keratinized epithelial cells in plaques together with unculi frequently exfoliate at the surface. The epidermis in furrows is equipped with secretory glandular cells, that is, mucous goblet cells, sacciform cells and club cells; and sensory structures, that is, the taste buds. These glandular cells are involved in the elaboration of different types of carbohydrate and protein moieties. Further, in the epidermis of both, plaques and furrows, melanophores are frequently interspersed between the epithelial cells. In the plaque epidermis, in addition to melanophores, melanin granules are observed in epithelial cells undergoing keratinization as well as in those sloughing at the surface. Sloughing of keratinized epithelial cells together with spine-like unculi at the surface of the plaques; the secretions of the glandular cells, the distribution of melanophore and the taste buds interspersed between the epithelial cells and the presence of melanin granules in the keratinized epithelial cells have been associated with different functional roles. These include hydrodynamic advantage, protection from mechanical stress, pathogens, UV radiation, localization of food accurately and so on in relation to the natural habitat of the fish.
本研究采用扫描电子显微镜、组织学、组织化学和免疫荧光技术对山女鳚的表皮进行了研究。表皮特征性地分化为斑块，斑块之间由深沟隔开。在斑块中，表皮角质化。相比之下，在沟中，它是粘蛋白生成的。斑块中的表面上皮细胞会变成具有特征性的刺状小刺。在这些小刺的远端，我们发现树状分支的树突状结构。斑块中的角质化上皮细胞和小刺经常在表面脱落。沟中的表皮配备有分泌腺细胞，即粘液杯状细胞、囊状细胞和棒状细胞；以及感觉结构，即味蕾。这些腺细胞参与不同类型碳水化合物和蛋白质部分的产生。此外，在斑块和沟的表皮中，黑色素细胞经常散布在上皮细胞之间。在斑块表皮中，除了黑色素细胞外，还观察到正在角质化的上皮细胞以及在表面脱落的上皮细胞中有黑色素颗粒。斑块表面的角质化上皮细胞和刺状小刺的脱落；腺细胞的分泌物、黑色素细胞的分布以及散布在上皮细胞之间的味蕾和角质化上皮细胞中的黑色素颗粒与鱼类的自然栖息地有关的不同功能角色有关。这些功能包括水动力优势、保护免受机械应激、病原体、紫外线辐射、食物的准确定位等。
