Retinoid requirements for recovery of sensitivity after visual-pigment bleaching in isolated photoreceptors.
AUTOR(ES)
Jones, G J
RESUMO
After visual-pigment bleaching, single isolated rod photoreceptors of Ambystoma tigrinum recover their sensitivity to light when supplied with 11-cis-retinal from liposomes or with 11-cis-retinal bound to interphotoreceptor retinoid-binding protein. Bleached rods do not recover sensitivity, or do so only very slowly, after exposure to 11-cis-retinol. The latter retinoid is "toxic" in that rods actually lose sensitivity in its presence. In contrast, bleached isolated cone cells recover sensitivity when either retinoid is supplied. It is suggested that the major pathway for rhodopsin regeneration during dark adaptation in the intact eye is transport of 11-cis-retinal from the pigment epithelium to the retina. The results also suggest that there may be separate pathways for visual-pigment regeneration in rods and cones during dark adaptation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=298547Documentos Relacionados
- Spatial localization of bleaching adaptation in isolated vertebrate rod photoreceptors.
- Visual transduction in human rod photoreceptors.
- Interphotoreceptor retinoid-binding protein promotes rhodopsin regeneration in toad photoreceptors.
- Role of cytoplasmic calcium concentration in the bleaching adaptation of salamander cone photoreceptors.
- An A−71C substitution in a green gene at the second position in the red/green visual-pigment gene array is associated with deutan color-vision deficiency