Purchase this article with an account.
J.B. Hurley, S. Kawamura, A. Sampath, J. Chen, F. Rieke; The influence of recoverin on visual sensitivity . Invest. Ophthalmol. Vis. Sci. 2004;45(13):2208.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To evaluate the biochemical and physiological functions of recoverin in rods and to evaluate the contribution of rod photoresponse kinetics to rod bipolar responses and to overall visual sensitivity. Methods: Phosphorylation of rhodopsin was measured in normal and recoverin–deficient retinas 1.0 sec after a moderate intensity flash. Rod responses were measured by ERG and by suction electrode recording. Rod bipolar responses from retinal slices were recorded with whole–cell and perforated–patch electrodes. Visual sensitivity was measured using mice trained to use visual cues to find a platform in a swim maze (Hayes and Balkema, (1993). Behav. Genet. 23:395). Results: Phosphorylation of rhodopsin is enhanced in recoverin–deficient mice consistent with the proposed role of recoverin as a regulator of rhodopsin kinase. ERG recordings and recordings from retinal slices indicate that the sensitivities of the rising phases of the rod response and of the rod–bipolar responses are normal in recoverin–deficient retinas. However, responses from individual rods and rod bipolar cells in recoverin–deficient retinas are shorter than in wild–type retinas. Recoverin–deficient mice require >2–fold more light than wild–type mice to use vision to find a platform in a swim maze. Conclusions: Recoverin delays phosphorylation of rhodopsin in dark–adapted rods and prolongs the rod outer segment light response. Rod bipolar responses are also prolonged by the presence of recoverin in rods. The presence of recoverin enhances the ability of mice to detect visual cues in very dim light. These findings suggest that prolongation of photoresponses by recoverin improves the sensitivity of rod–mediated vision in mice.
This PDF is available to Subscribers Only