2024, Vol. 5, Issue 1, Part C
Pineal of fish Bagarius bagarius (Hamilton) and structure of photoreceptor cell
Author(s): Awadhesh Singh Yadav and Rajesh Kumar Dubey
Abstract: The pineal organ of fish Bagarius bagarius is situated in the cranium in the undersurface of skin covering pineal foramen and consists of pineal sac, pineal thalamus and pineal stalk. The pineal sac is trilobed rossette like with swollen base and surrounded by connective tissue capsule. The parenchymatous layer of lateral and ventral wall are thick dorsal wall is thin. Villi from latero-ventral wall protrude into the lumen which contains photoreceptor, supporting, astrocyte, ganglion and endothelial cells. The thalamus is swollen base of sac and the stalk is long thread like structure. The photoreceptor cells are elongated cucumber shaped consisting of dumble-shaped inner segment and outer segment. Inner segment has a nucleatd basal lobe with a irrigular wavy indented nuclear membrane, a cytoplasm with rich golgi bodies, globular vesicles, rough walled endoplasmic reticulum, Alfa and Beta granules, less number of oval mitochondria with reticulate cristae and lysosome, synaptic terminals are present at the base which join with processes of Ganglion cells. The non-nucleated apical lobe of inner segment is densely packed with mitochondria and is constricted at the junction of basal lobe forming "Terminal bar" serving as junction for neighbouring supporting cells. The outer lamellar segment is attached with the apical lobe of inner segment through ciliary connecting process. The attachment is cone like. The outer segment is ciliary tubular, partially lamellar, swirling, isolating lamellar, modifying lamellar, wholly lamellar, distorting and exhausted type under Transmission electron microscopic observation. Under scanning electron microscopic observation the fractured pineal sac shows lumen with various shapes of outer segment like oval, spherical, spherical bilobed, bean-shaped, moon-shaped, circular narrow at both end and irregular rectangular. Presence of large number of mitochondria, Alfa and Beta glycogen particle indicate their role in storage as well as oxidative phosphorylation and cone like arrangement indicate photoreceptive function.
DOI: 10.33545/27080013.2024.v5.i1c.201
Pages: 253-258 | Views: 60 | Downloads:
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How to cite this article:
Awadhesh Singh Yadav, Rajesh Kumar Dubey. Pineal of fish Bagarius bagarius (Hamilton) and structure of photoreceptor cell. Acta Entomol Zool 2024;5(1):253-258. DOI: 10.33545/27080013.2024.v5.i1c.201
