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. 1975 Oct 1;66(4):407–425. doi: 10.1085/jgp.66.4.407

Light-sensitive swelling of isolated frog rod outer segments as an in vitro assay for visual transduction and dark adaptation

PMCID: PMC2226212  PMID: 52687

Abstract

Frog rod outer segments swell slowly after being shaken from an excised retina into a modified Ringer's solution. The swelling has the following characteristics: (a) It is suppressed by illumination which bleaches only 500 rhodopsin molecules per outer segment per second. This is approximately the level required to saturate the in vivo receptor potential. (b) Light suppression is seen in NaCl but not in KCl solutions. (c) Dark swelling is labile and is enhanced by calf serum, low calcium concentrations, dithiothreitol, and cyclic nucleotide phosphodiesterase inhibitors. (d) Lowering the pH to 5.5 or removing magnesium reversibly reduces dark swelling to the same extent as illumination. (e) The amount of light required for maximal suppression of dark-swelling increases approximately 10-fold if the calcium concentrations is lowered by EGTA addition. (f) The effect of illumination is irreversibly abolished by antimycin and other inhibitors of mitochondrial electron transport. (g) A process analogous to dark adaptation in vivo can be observed: If 10-50% of the rhodopsin present is bleached and the outer segments are then kept dark, rapid dark swelling returns after a period of 15-45 min. This swelling is again sensitive to light. We tentatively ascribe the light suppression of swelling to the same decrease in sodium permeability which is observed on illuminating living receptor cells. The experiments suggest that outer segments retain their competence to perform both transduction and dark adaptation after their separation from the retina.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bownds D., Brodie A., Robinson W. E., Palmer R. D., Miller J., Shedlovsky A. Proceedings: Physiology and enzymology of frog photoreceptor membranes. Exp Eye Res. 1974 Mar;18(3):253–269. doi: 10.1016/0014-4835(74)90153-5. [DOI] [PubMed] [Google Scholar]
  2. Bownds D., Dawes J., Miller J., Stahlman M. Phosphorylation of frog photoreceptor membranes induced by light. Nat New Biol. 1972 May 24;237(73):125–127. doi: 10.1038/newbio237125a0. [DOI] [PubMed] [Google Scholar]
  3. Bownds D., Gordon-Walker A., Gaide-Huguenin A. C., Robinson W. Characterization and analysis of frog photoreceptor membranes. J Gen Physiol. 1971 Sep;58(3):225–237. doi: 10.1085/jgp.58.3.225. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Daemen F. J. Vertebrate rod outer segment membranes. Biochim Biophys Acta. 1973 Nov 28;300(3):255–288. doi: 10.1016/0304-4157(73)90006-3. [DOI] [PubMed] [Google Scholar]
  5. Frank R. N., Cavanagh H. D., Kenyon K. R. Light-stimulated phosphorylation of bovine visual pigments by adenosine triphosphate. J Biol Chem. 1973 Jan 25;248(2):596–609. [PubMed] [Google Scholar]
  6. Hagins W. A. The visual process: Excitatory mechanisms in the primary receptor cells. Annu Rev Biophys Bioeng. 1972;1:131–158. doi: 10.1146/annurev.bb.01.060172.001023. [DOI] [PubMed] [Google Scholar]
  7. Hagins W. A., Yoshikami S. Proceedings: A role for Ca2+ in excitation of retinal rods and cones. Exp Eye Res. 1974 Mar;18(3):299–305. doi: 10.1016/0014-4835(74)90157-2. [DOI] [PubMed] [Google Scholar]
  8. Korenbrot J. I., Brown D. T., Cone R. A. Membrane characteristics and osmotic behavior of isolated rod outer segments. J Cell Biol. 1973 Feb;56(2):389–398. doi: 10.1083/jcb.56.2.389. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Korenbrot J. I., Cone R. A. Dark ionic flux and the effects of light in isolated rod outer segments. J Gen Physiol. 1972 Jul;60(1):20–45. doi: 10.1085/jgp.60.1.20. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kühn H., Cook J. H., Dreyer W. J. Phosphorylation of rhodopsin in bovine photoreceptor membranes. A dark reaction after illumination. Biochemistry. 1973 Jun 19;12(13):2495–2502. doi: 10.1021/bi00737a020. [DOI] [PubMed] [Google Scholar]
  11. Miki N., Keirns J. J., Marcus F. R., Freeman J., Bitensky M. W. Regulation of cyclic nucleotide concentrations in photoreceptors: an ATP-dependent stimulation of cyclic nucleotide phosphodiesterase by light. Proc Natl Acad Sci U S A. 1973 Dec;70(12):3820–3824. doi: 10.1073/pnas.70.12.3820. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Normann R. A., Werblin F. S. Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and cones. J Gen Physiol. 1974 Jan;63(1):37–61. doi: 10.1085/jgp.63.1.37. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Pannbacker R. G. Control of guanylate cyclase activity in the rod outer segment. Science. 1973 Dec 14;182(4117):1138–1140. doi: 10.1126/science.182.4117.1138. [DOI] [PubMed] [Google Scholar]
  14. Reed P. W., Lardy H. A. A23187: a divalent cation ionophore. J Biol Chem. 1972 Nov 10;247(21):6970–6977. [PubMed] [Google Scholar]
  15. Wald G. Molecular basis of visual excitation. Science. 1968 Oct 11;162(3850):230–239. doi: 10.1126/science.162.3850.230. [DOI] [PubMed] [Google Scholar]

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