VITAMIN A DEFICIENCY AND NIGHT BLINDNESS

Abstract

This study maps the entire course of vitamin A deficiency and its cure in the rat. In single groups of animals, the vitamin A in the liver and blood, the retinal content of rhodopsin and opsin, the electroretinographic threshold, and the ERG''s (electroretinogram) obtained over a wide range of light intensities were measured simultaneously. In key instances the retinal histology were also examined. Experiments revealed a direct relationship between availability of vitamin A and certain body changes, pointing to a general and fundamental (but yet unknown) function of the vitamin in tissues all over the body.