M. Carter Cornwall

Research

Dark Adaptation in Vertebrate Photoreceptors

The work in our laboratory is focused on understanding the response of the vertebrate eye to and recovery from the effects of bright light. Our principal approach is to make electrophysiological measurements of rod and cone photoreceptors of cold-blooded vertebrate animals, and to correlate these physiological responses to microspectrophotomeric measurements of the visual pigments as well as microfluorometric measurements of the concentration of vitamin A and Ca2+ contained within the cells. The reduction of all–trans retinal to Vitamin A is one of the principal initial steps that must occur following exposure to bright light to allow recovery of sensitivity (dark adaptation). Experiments have also shown that Ca2+ is a principal messenger substance during bright (bleaching) adaptation.