[Mechanism of signal transduction in photoreceptors of vertebrates: identification of an intracellular transmitter].
A short account is given of the studies which resulted in identification of cGMP as intracellular transmitter which realizes the control of light-depending channels of vertebrate photoreceptors. The following problems are discussed. 1. Proofs of necessary participation of intracellular mediator in the signal transduction in the photoreception act. 2. Competition between cGMP and Ca2+ ions for the role of such mediator in the photoreceptors of vertebrates. Relationship between metabolism of cGMP and Ca2+ which makes impossible identification of the mediator in the in vivo experiments. 3. Patch-clamp-experiments which have shown that conductivity of the rod plasma membrane is controlled by cGMP rather than by Ca2+ ions. Proofs of the identity of cGMP-regulated channels recorded in patch-clamp-experiments and light-dependent channels observed in the in vivo experiments. 4. Analysis of the prospects of further studies of the control mechanism of light-dependent channels.
D000818:Animals; D006152:Cyclic GMP / Q000378:metabolism*; D007473:Ion Channels / Q000378:metabolism; D008954:Models, Biological; D010775:Photic Stimulation; D010786:Photoreceptor Cells / Q000378:metabolism*; D014714:Vertebrates
D007473:Ion Channels; D006152:Cyclic GMP
Mekhanizm transduktsii signala v fotoretseptorakh pozvonochnykh: identifikatsiia vnutrikletochnogo mediatora.