Melatonin modulates glycine currents of retinal ganglion cells in rat.
Melatonin is a hormone participating in the modulation of various physiological functions via binding to specific melatonin receptors. In the retina, melatonin is synthesized and released by photoreceptors and may play a neuromodulatory role. By using patch clamp techniques, we demonstrate for the first time that glycine-induced currents from a population of isolated ganglion cells in the rat retina are potentiated by melatonin of nanomolar concentrations by increasing the efficacy and the channel conductance of the strychnine-sensitive glycine receptor. The melatonin effect is blocked by 4-P-PDOT, indicating the mediation of the MT2 receptor. These results suggest that melatonin, along with the MT2 receptor, may be involved in retinal information processing by modulating glycine receptor-mediated inhibition.
Zhang
Min
M
Institute of Neurobiology, Fudan University, Shanghai, P.R. China.
Cao
Li-Hui
LH
Yang
Xiong-Li
XL
D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology; D008550:Melatonin / Q000378:metabolism* / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D018408:Patch-Clamp Techniques; D051381:Rats; D044123:Receptor, Melatonin, MT2 / Q000187:drug effects / Q000378:metabolism; D018009:Receptors, Glycine / Q000187:drug effects / Q000378:metabolism*; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology; D014785:Vision, Ocular / Q000502:physiology
D044123:Receptor, Melatonin, MT2; D018009:Receptors, Glycine; D008550:Melatonin