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Loss of caveolin-1 impairs retinal function due to disturbance of subretinal microenvironment.

ABSTRACT: Caveolin-1 (Cav-1), an integral component of caveolar membrane domains, is expressed in several retinal cell types, including photoreceptors, retinal vascular endothelial cells, Müller glia, and retinal pigment epithelium (RPE) cells. Recent evidence links Cav-1 to ocular diseases, including autoimmune uveitis, diabetic retinopathy, and primary open angle glaucoma, but its role in normal vision is largely undetermined. In this report, we show that ablation of Cav-1 results in reduced inner and outer retinal function as measured, in vivo, by electroretinography and manganese-enhanced MRI. Somewhat surprisingly, dark current and light sensitivity were normal in individual rods (recorded with suction electrode methods) from Cav-1 knock-out (KO) mice. Although photoreceptor function was largely normal, in vitro, the apparent K(+) affinity of the RPE-expressed ?1-Na(+)/K(+)-ATPase was decreased in Cav-1 KO mice. Cav-1 KO retinas also displayed unusually tight adhesion with the RPE, which could be resolved by brief treatment with hyperosmotic medium, suggesting alterations in outer retinal fluid homeostasis. Collectively, these findings demonstrate that reduced retinal function resulting from Cav-1 ablation is not photoreceptor-intrinsic but rather involves impaired subretinal and/or RPE ion/fluid homeostasis.

SUBMITTER: Li X

PROVIDER: S-EPMC3351350 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Loss of caveolin-1 impairs retinal function due to disturbance of subretinal microenvironment.

Li Xiaoman X McClellan Mark E ME Tanito Masaki M Garteiser Philippe P Towner Rheal R Bissig David D Berkowitz Bruce A BA Fliesler Steven J SJ Woodruff Michael L ML Fain Gordon L GL Birch David G DG Khan M Suhaib MS Ash John D JD Elliott Michael H MH

The Journal of biological chemistry 20120326 20

Caveolin-1 (Cav-1), an integral component of caveolar membrane domains, is expressed in several retinal cell types, including photoreceptors, retinal vascular endothelial cells, Müller glia, and retinal pigment epithelium (RPE) cells. Recent evidence links Cav-1 to ocular diseases, including autoimmune uveitis, diabetic retinopathy, and primary open angle glaucoma, but its role in normal vision is largely undetermined. In this report, we show that ablation of Cav-1 results in reduced inner and o ...[more]

PMID: 22451674

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Dataset Information

Loss of caveolin-1 impairs retinal function due to disturbance of subretinal microenvironment.

Publications

Loss of caveolin-1 impairs retinal function due to disturbance of subretinal microenvironment.

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