Effects of cyclic adenosine 3',5'-monophosphate on photoreceptor disc shedding and retinomotor movement. Inhibition of rod shedding and stimulation of cone elongation. J Gen Physiol 1982 May;79(5):775-90
Date
05/01/1982Pubmed ID
6284860Pubmed Central ID
PMC2215507DOI
10.1085/jgp.79.5.775Scopus ID
2-s2.0-0020055718 (requires institutional sign-in at Scopus site) 62 CitationsAbstract
As a test of the hypothesis that cyclic nucleotides play a role in the regulation of retinomotor movements and disc shedding in the photoreceptor-pigment epithelial complex, we have used an in vitro eyecup preparation that sustains both disc shedding and cone retinomotor movements, Eyecups were prepared in white light from animals in which both shedding and cone movement had been blocked by 4 d of constant-light treatment. In eyecups incubated for 3 h in light, disc shedding was negligible and cones remained in the light-adapted (contracted) position. In eyecups incubated in darkness, however, a massive shedding response (dominated by rod photoreceptors) was induced, and at the same time cone photoreceptors elongated to their dark-adapted position. In eyecups incubated in light dbcAMP promoted cone elongation and thus mimicked darkness; the dbcAMP effect was potentiated by the phosphodiesterase inhibitors papaverine and 3-isobutylmethylxanthine. In eyecups incubated in darkness, on the other hand, both phosphodiesterase inhibitors and dbcAMP reduced the phagosome content of the pigment epithelium. The effects of dbcAMP on the cone elongation and rod shedding appear to be specific in that dbcGMP, adenosine, and adenosine 5'-monophosphate had no significant effect. Our results suggest that cAMP plays a role in the regulation of both retinomotor movements and disc shedding.
Author List
Besharse JC, Dunis DA, Burnside BMESH terms used to index this publication - Major topics in bold
AnimalsCyclic AMP
Darkness
In Vitro Techniques
Light
Photoreceptor Cells
Pigment Epithelium of Eye
Retina
Xenopus laevis
