Analysis of rapid off-response in electroretinogram major participation of receptor potential
Kawasaki, K.; Yonemura, D.; Nakazato, H.; Wakabayashi, K.; Shirao, Y.; Sakai, N.
Nippon Ganka Gakkai Zasshi 84(10): 1574-1580
1980
ISSN/ISBN: 0029-0203 PMID: 7257974 Document Number: 161924
The rapidly positive-going off-response in the electroretinogram in the monkey and human was reportedly composed mainly of the decay of the late receptor potential of cones. The off-wavelets superimposing upon the rapid off-response was previously found to modify the amplitude of the rapid off-response. The off-wavelets, like the oscillatory potential as on-wavelets, were probably postsynaptic in generation mechanism, since they were readily abolished in the monkey (Macaca irus) by sodium aspartate, which blocked retinal synaptic transmission, keeping the receptor potential intact. The latency and slope of the initial rising phase of the rapid off-response remained unchanged by aspartate. The initial peak of the rapid off-response was slightly delayed and enhanced after the abolition of the off-wavelets by aspartate. The difference between the amplitudes of the rapid decay before and after the aspartate treatment was within about 15% in the monkey at an optimal stimulus parameter (600-1000 lx at the retina, stimulus frequency 2Hz and stimulus duration 250 ms). The anplitude of the rapid off-response was slightly (10-20%) larger in the affected eye in cases of monocular occlusion of the central retinal artery than in the healthy fellow eye. The rapid off-response apparently consists mainly of the cone late receptor potential. The rapid off-response is of clinical use in an objective and quantitative estimation of the photopic system at the receptor level.