Effect of dark and light adaptation on the retina and pecten of chicken

Article (PDF Available)inExperimental Eye Research 13(1):92-7 · February 1972with662 Reads
DOI: 10.1016/0014-4835(72)90129-7 · Source: PubMed
Abstract
Retinae and pecten oculi of chickens were studied after 30 days of dark and light adaptation. Biochemically, glycogen and alkaline phosphatase activity increased 24 and 6%, respectively, in retina on dark adaptation, and decreased 15 and 17%, respectively, on light adaptation. Retinal RNA content increased 11% on light adaptation. DNA remained unaffected on dark and light adaptation of the retina. Alkaline phosphatase activity of pecten decreased 25% on dark adaptation.Histochemically, glycogen-rich paraboloids of accessory cones and hyperboloids of rods of the retina atrophied when subjected to light and hypertrophied on dark adaptation. On light adaptation, except for the outer plexiform layer, the alkaline phosphatase activity was negligible. Possible significance of these results in relation to sensory functions of the retina and retina-pecten interrelationship is discussed.

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Available from: Rakesh Yashroy
    • "It has suggested that pigmented cells provide the structural reinforcement to pecten oculi for keeping it firmly erectile within the gel-like vitreous and also protect the blood vessels against damage from ultraviolet light [1, 7, 17]. In addition the absorption of light by the pigmented cells probably raises the temperature within the pecten and hence the rate of metabolism within it [19]. This research provides data concerning the anatomical and histological characteristics of pecten oculi of different avian species. "
    [Show abstract] [Hide abstract] ABSTRACT: In this study was investigated the structure of pecten oculi in the ostrich, duck, pigeon, turkey, and starling. The pecten oculi of the ostrich was vaned type and made up primary, secondary, and few tertiary lamellae. However, duck, pigeon, turkey and starling had a pleated-type pecten oculi which displayed folded structure. The numbers of pleats of the pectens were 12, 13-14, 21-22, and 17 in duck, pigeon, turkey, and starling, respectively. Light microscopic investigation demonstrated that pecten oculi is basically composed of numerous capillaries, large blood vessels, and pigment cells in all investigating avian species. Capillaries were 20.23, 14.34, 11.78, 12.58, and 12.78 μ m in diameter in ostrich, duck, pigeon, turkey, and starling, respectively. The capillaries are surrounded by thick basal membrane, and pigmented cells were observed around the capillaries.
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