Physiological evidence that light-mediated decrease in cyclic GMP is an intermediary process in retinal rod transduction.
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چکیده
منابع مشابه
Physiological evidence that light-mediated decrease in cyclic GMP is an intermediary process in retinal rod transduction
Brief, intracellularly injected pulses of cyclic GMP transiently depolarized toad retinal rod outer segments (ROS). The depolarization is antagonized by light, perhaps by the activation of phosphodiesterase (PDE), as shown in the biochemical studies of others. As measured by the antagonism of cyclic GMP pulses by light, PDE activity peaks after the peak of the receptor potential and has approxi...
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Knowledge of the kinetics of the rod cyclic GMP phosphodiesterase is essential for understanding the kinetics and gain of the light response. Therefore, the interactions between Mg2+, cyclic GMP, and purified, trypsin-activated bovine rod cyclic GMP phosphodiesterase (EC 3.1.4.17) were examined. The effects of Mg2+ and of cyclic GMP on the rod phosphodiesterase activity were mutually concentrat...
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Cyclic GMP (cGMP) is the intracellular messenger that mediates phototransduction in retinal rods. As photoisomerizations of rhodopsin molecules are local events, the longitudinal diffusion of cGMP in the rod outer segment should be a contributing factor to the response of the cell to light. We have employed the truncated rod outer segment preparation from bullfrog (Rana catesbeiana) and tiger s...
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ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 1982
ISSN: 0022-1295,1540-7748
DOI: 10.1085/jgp.80.1.103