Characterization of serine's inhibitory action on neurons in the mudpuppy retina.
Experiments were performed in the superfused retina-eyecup of mudpuppies using intracellular electrophysiological techniques to evaluate the effects of serine on amacrine and ganglion cells. Serine was found to have a dose-dependent inhibitory effect mediated by the opening of chloride channels. Serine appears to act on a glycine receptor based on the observations that: (1) serine's effect is blocked by strychnine but not by bicuculline or picrotoxin, (2) in the presence of saturating glycine concentrations serine had no effect on membrane voltage or conductance, and (3) cells inhibited by serine were always sensitive to glycine, but not always sensitive to GABA. High pressure liquid chromatography measurements disclose that there is a high concentration of extracellular serine in the retina. The data indicate that serine could act as an inhibitory neurotransmitter.
Slaughter
M M
MM
Department of Biophysical Sciences, School of Medicine, State University of New York, Buffalo 14214.
Miller
R F
RF
D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D001640:Bicuculline / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D003035:Cobalt / Q000494:pharmacology; D003624:Darkness; D004553:Electric Conductivity / Q000187:drug effects; D005074:Evoked Potentials, Visual / Q000187:drug effects; D005973:Glutamine / Q000494:pharmacology; D005998:Glycine / Q000494:pharmacology; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009337:Necturus; D010775:Photic Stimulation; D012160:Retina / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000502:physiology*; D012694:Serine / Q000494:pharmacology*; D013331:Strychnine / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D005973:Glutamine; D001224:Aspartic Acid; D003035:Cobalt; D012694:Serine; D005680:gamma-Aminobutyric Acid; D013331:Strychnine; D002118:Calcium; D005998:Glycine; D001640:Bicuculline