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

Department of Biophysics, Panjab University, Chandigarh, India
Experimental Eye Research (Impact Factor: 3.02). 02/1972; 13(1):92-7. 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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