Skip to main content
NCBI home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1977 Feb;265(1):85–102. doi: 10.1113/jphysiol.1977.sp011706

Effects of applied currents on turtle cones in darkness and during the photoresponse.

A L Byzov, L Cervetto
PMCID: PMC1307809  PMID: 850195

Abstract

1. The voltage changes, produced by pulses of current of various intensities and polarities into turtle cones, were examined both in darkness and during the photoresponse. 2. Depolarizing pulses of current produced voltage deflexions which, during the photoresponse, were increased to a greater extent than those produced by pulses of current of the same intensity and opposite polarity. 3. Voltage-current relationships were measured both in darkness and during illumination. During illumination they display a non-linear behaviour, the curve being steeper for positive than for negative currents. 4. These non-linearities are greatly attenuated following exposure of the retina to a solution containing 5 mM-CoCl2 which is known to block synaptic transmission. The effects of CoCl2 are readily reversible when the retina is returned to normal conditions. 5. By comparing the effects produced by pulses of current injected into individual cones with those observed in horizontal cells following stimulation with a radial current, it is observed that the non-linear behaviour of the cone membrane during the photoresponse can be, at least in part, accounted for by events occurring in post-synaptic elements (i.e. horizontal cells).

Full text

PDF
85

Images in this article

102-1Plate 1
on p.102-1

Selected References

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

  1. Arden G. B., Ernst W. The effect of ions on the photoresponses of pigeon cones. J Physiol. 1970 Dec;211(2):311–339. doi: 10.1113/jphysiol.1970.sp009281. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Baylor D. A., Fuortes M. G. Electrical responses of single cones in the retina of the turtle. J Physiol. 1970 Mar;207(1):77–92. doi: 10.1113/jphysiol.1970.sp009049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Baylor D. A., Fuortes M. G., O'Bryan P. M. Receptive fields of cones in the retina of the turtle. J Physiol. 1971 Apr;214(2):265–294. doi: 10.1113/jphysiol.1971.sp009432. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Baylor D. A., Hodgkin A. L., Lamb T. D. Reconstruction of the electrical responses of turtle cones to flashes and steps of light. J Physiol. 1974 Nov;242(3):759–791. doi: 10.1113/jphysiol.1974.sp010733. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Baylor D. A., Hodgkin A. L., Lamb T. D. The electrical response of turtle cones to flashes and steps of light. J Physiol. 1974 Nov;242(3):685–727. doi: 10.1113/jphysiol.1974.sp010731. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bortoff A., Norton A. L. An electrical model of the vertebrate photoreceptor cell. Vision Res. 1967 Mar;7(3):253–263. doi: 10.1016/0042-6989(67)90089-2. [DOI] [PubMed] [Google Scholar]
  7. Byzov A. L., Trifonov J. A. The response to electric stimulation of horizontal cells in the carp retina. Vision Res. 1968 Jul;8(7):817–822. doi: 10.1016/0042-6989(68)90132-6. [DOI] [PubMed] [Google Scholar]
  8. Byzov A. L., Trifonov J. A. The response to electric stimulation of horizontal cells in the carp retina. Vision Res. 1968 Jul;8(7):817–822. doi: 10.1016/0042-6989(68)90132-6. [DOI] [PubMed] [Google Scholar]
  9. Byzov A. L. Vzaimodeistvie mezhdu gorizontal'nymi kletkami setchatki cherepakhi. Neirofiziologiia. 1975;7(3):279–286. [PubMed] [Google Scholar]
  10. Cervetto L. Influence of sodium, potassium and chloride ions on the intracellular responses of turtle photoreceptors. Nature. 1973 Feb 9;241(5389):401–403. doi: 10.1038/241401a0. [DOI] [PubMed] [Google Scholar]
  11. Cervetto L., Piccolino M. Synaptic transmission between photoreceptors and horizontal cells in the turtle retina. Science. 1974 Feb 1;183(4123):417–419. doi: 10.1126/science.183.4123.417. [DOI] [PubMed] [Google Scholar]
  12. FRANK K., FUORTES M. G. Stimulation of spinal motoneurones with intracellular electrodes. J Physiol. 1956 Nov 28;134(2):451–470. doi: 10.1113/jphysiol.1956.sp005657. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Fuortes M. G., Schwartz E. A., Simon E. J. Colour-dependence of cone responses in the turtle retina. J Physiol. 1973 Oct;234(1):199–216. doi: 10.1113/jphysiol.1973.sp010341. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Lasansky A., Marchiafava P. L. Light-induced resistance changes in retinal rods and cones of the tiger salamander. J Physiol. 1974 Jan;236(1):171–191. doi: 10.1113/jphysiol.1974.sp010429. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. O'Bryan P. M. Properties of the depolarizing synaptic potential evoked by peripheral illumination in cones of the turtle retina. J Physiol. 1973 Nov;235(1):207–223. doi: 10.1113/jphysiol.1973.sp010385. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Penn R. D., Hagins W. A. Signal transmission along retinal rods and the origin of the electroretinographic a-wave. Nature. 1969 Jul 12;223(5202):201–204. doi: 10.1038/223201a0. [DOI] [PubMed] [Google Scholar]
  17. Sillman A. J., Ito H., Tomita T. Studies on the mass receptor potential of the isolated frog retina. II. On the basis of the ionic mechanism. Vision Res. 1969 Dec;9(12):1443–1451. doi: 10.1016/0042-6989(69)90060-1. [DOI] [PubMed] [Google Scholar]
  18. Simon E. J. Two types of luminosity horizontal cells in the retina of the turtle. J Physiol. 1973 Apr;230(1):199–211. doi: 10.1113/jphysiol.1973.sp010183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Toyoda J., Nosaki H., Tomita T. Light-induced resistance changes in single photoreceptors of Necturus and Gekko. Vision Res. 1969 Apr;9(4):453–463. doi: 10.1016/0042-6989(69)90134-5. [DOI] [PubMed] [Google Scholar]
  20. Werblin F. S. Regenerative hyperpolarization in rods. J Physiol. 1975 Jan;244(1):53–81. doi: 10.1113/jphysiol.1975.sp010784. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES