| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
The electroretinogram (ERG) of anaesthetised dark-adapted macaque monkeys was recorded in response to ganzfeld stimulation and rod- and cone-driven receptoral and postreceptoral components were separated and modelled. The test stimuli were brief (< 4.1 ms) flashes. The cone-driven component was isolated by delivering the stimulus shortly after a rod-saturating background had been extinguished. The rod-driven component was derived by subtracting the cone-driven component from the mixed rod-cone ERG. The initial part of the leading edge of the rod-driven a-wave scaled linearly with stimulus energy when energy was sufficiently low and, for times less than about 12 ms after the stimulus, it was well described by a linear model incorporating a distributed delay and three cascaded low-pass filter elements. Addition of a simple static saturating non-linearity with a characteristic intermediate between a hyperbolic and an exponential function was sufficient to extend application of the model to most of the leading edge of the saturated responses to high energy stimuli. It was not necessary to assume involvement of any other non-linearity or that any significant low-pass filter followed the non-linear stage of the model. A negative inner-retinal component contributed to the later part of the rod-driven a-wave. After suppressing this component by blocking ionotropic glutamate receptors, the entire a-wave up to the time of the first zero-crossing scaled with stimulus energy and was well described by summing the response of the rod model with that of a model describing the leading edge of the rod-bipolar cell response. The negative inner-retinal component essentially cancelled the early part of the rod-bipolar cell component and, for stimuli of moderate energy, made it appear that the photoreceptor current was the only significant component of the leading edge of the a-wave. The leading edge of the cone-driven a-wave included a slow phase that continued up to the peak, and was reduced in amplitude either by a rod-suppressing background or by the glutamate analogue, cis-piperidine-2,3-dicarboxylic acid (PDA). Thus the slow phase represents a postreceptoral component present in addition to a fast component of the a-wave generated by the cones themselves. At high stimulus energies, it appeared less than 5 ms after the stimulus. The leading edge of the cone-driven a-wave was adequately modelled as the sum of the output of a cone photoreceptor model similar to that for rods and a postreceptoral signal obtained by a single integration of the cone output. In addition, the output of the static non-linear stage in the cone model was subject to a low-pass filter with a time constant of no more than 1 ms. In conclusion, postreceptoral components must be taken into account when interpreting the leading edge of the rod- and cone-driven a-waves of the dark-adapted ERG.
This article has been cited by other articles:
|
|
 |
|
  F. Rieke, A. Lee, and F. Haeseleer Characterization of Ca2+-Binding Protein 5 Knockout Mouse Retina Invest. Ophthalmol. Vis. Sci., November 1, 2008; 49(11): 5126 - 5135. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Fortune, G. A. Cull, and C. F. Burgoyne Relative Course of Retinal Nerve Fiber Layer Birefringence and Thickness and Retinal Function Changes after Optic Nerve Transection Invest. Ophthalmol. Vis. Sci., October 1, 2008; 49(10): 4444 - 4452. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. T. O. Nguyen, A. J. Vingrys, and B. V. Bui Dietary Omega-3 Fatty Acids and Ganglion Cell Function Invest. Ophthalmol. Vis. Sci., August 1, 2008; 49(8): 3586 - 3594. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Nishihara, M. Kondo, K. Ishikawa, T. Sugita, C.-H. Piao, Y. Nakamura, and H. Terasaki Focal Macular Electroretinograms in Eyes with Wet-type Age-Related Macular Degeneration Invest. Ophthalmol. Vis. Sci., July 1, 2008; 49(7): 3121 - 3125. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. K. Mojumder, D. M. Sherry, and L. J. Frishman Contribution of voltage-gated sodium channels to the b-wave of the mammalian flash electroretinogram J. Physiol., May 15, 2008; 586(10): 2551 - 2580. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. G. Gregg, M. Kamermans, J. Klooster, P. D. Lukasiewicz, N. S. Peachey, K. A. Vessey, and M. A. McCall Nyctalopin Expression in Retinal Bipolar Cells Restores Visual Function in a Mouse Model of Complete X-Linked Congenital Stationary Night Blindness J Neurophysiol, November 1, 2007; 98(5): 3023 - 3033. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. F. X. Goldberg, L. M. Ritter, N. Khattree, N. S. Peachey, R. N. Fariss, L. Dang, M. Yu, and A. R. Bottrell An Intramembrane Glutamic Acid Governs Peripherin/rds Function for Photoreceptor Disk Morphogenesis Invest. Ophthalmol. Vis. Sci., July 1, 2007; 48(7): 2975 - 2986. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Ikenoya, M. Kondo, C.-H. Piao, S. Kachi, Y. Miyake, and H. Terasaki Preservation of Macular Oscillatory Potentials in Eyes of Patients with Retinitis Pigmentosa and Normal Visual Acuity Invest. Ophthalmol. Vis. Sci., July 1, 2007; 48(7): 3312 - 3317. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. L. Duncan, H. Yang, T. Doan, R. S. Silverstein, G. J. Murphy, G. Nune, X. Liu, D. Copenhagen, B. L. Tempel, F. Rieke, et al. Scotopic visual signaling in the mouse retina is modulated by high-affinity plasma membrane calcium extrusion. J. Neurosci., July 5, 2006; 26(27): 7201 - 7211. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Phipps, P. Yee, E. L. Fletcher, and A. J. Vingrys Rod photoreceptor dysfunction in diabetes: activation, deactivation, and dark adaptation. Invest. Ophthalmol. Vis. Sci., July 1, 2006; 47(7): 3187 - 3194. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Y. Marmorstein, J. Wu, P. McLaughlin, J. Yocom, M. O. Karl, R. Neussert, S. Wimmers, J. B. Stanton, R. G. Gregg, O. Strauss, et al. The Light Peak of the Electroretinogram Is Dependent on Voltage-gated Calcium Channels and Antagonized by Bestrophin (Best-1) J. Gen. Physiol., April 24, 2006; 127(5): 577 - 589. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S Kenkre, N. A Moran, T. D Lamb, and O. A. R Mahroo Extremely rapid recovery of human cone circulating current at the extinction of bleaching exposures J. Physiol., August 15, 2005; 567(1): 95 - 112. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. V. Rangaswamy, L. J. Frishman, E. U. Dorotheo, J. S. Schiffman, H. M. Bahrani, and R. A. Tang Photopic ERGs in Patients with Optic Neuropathies: Comparison with Primate ERGs after Pharmacologic Blockade of Inner Retina Invest. Ophthalmol. Vis. Sci., October 1, 2004; 45(10): 3827 - 3837. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Friedburg, C. P. Allen, P. J. Mason, and T. D. Lamb Contribution of cone photoreceptors and post-receptoral mechanisms to the human photopic electroretinogram J. Physiol., May 1, 2004; 556(3): 819 - 834. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Ueno, M. Kondo, Y. Niwa, H. Terasaki, and Y. Miyake Luminance Dependence of Neural Components that Underlies the Primate Photopic Electroretinogram Invest. Ophthalmol. Vis. Sci., March 1, 2004; 45(3): 1033 - 1040. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Wu, N. S. Peachey, and A. D. Marmorstein Light-Evoked Responses of the Mouse Retinal Pigment Epithelium J Neurophysiol, March 1, 2004; 91(3): 1134 - 1142. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. V. Bui and B. Fortune Ganglion cell contributions to the rat full-field electroretinogram J. Physiol., February 15, 2004; 555(1): 153 - 173. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. A. R. Mahroo and T. D. Lamb Recovery of the human photopic electroretinogram after bleaching exposures: estimation of pigment regeneration kinetics J. Physiol., January 15, 2004; 554(2): 417 - 437. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. V. Rangaswamy, D. C. Hood, and L. J. Frishman Regional Variations in Local Contributions to the Primate Photopic Flash ERG: Revealed Using the Slow-Sequence mfERG Invest. Ophthalmol. Vis. Sci., July 1, 2003; 44(7): 3233 - 3247. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
