Neuronal discriminator formed by metabotropic gamma-aminobutyric acid receptors.
Neuronal discriminator formed by metabotropic gamma-aminobutyric acid receptors. J. Neurophysiol. 80: 3365-3368, 1998. Neurotransmitters function in one of two modes, promoting either inhibition or excitation. However, the metabotropic gamma-aminobutyric acid receptor (GABABR) system can switch between these modes. In the presence of a small excitatory stimulus, the GABABR mediates a shunting inhibition that suppresses excitation. However, in the presence of a strong excitatory stimulus, the GABABR potentiates the response. This bipartite action is accomplished by linking the GABABR to two electrogenic mechanisms; one activates an outward current and another reduces an outward current. As a consequence, the GABABR serves as a discriminator that reduces the influence of weak signals while augmenting responses to strong signals. In retinal ganglion cells, this mechanism acts to promote the communication of phasic information.
Zhang
J
J
Department of Physiology and Biophysics, School of Medicine, State University of New York, Buffalo, New York 14214, USA.
Tian
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N
Slaughter
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D000557:Ambystoma; D000818:Animals; D001418:Baclofen / Q000494:pharmacology; D002104:Cadmium / Q000494:pharmacology; D004558:Electric Stimulation; D004594:Electrophysiology; D018756:GABA Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000502:physiology; D018408:Patch-Clamp Techniques; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000502:physiology*; D013569:Synapses / Q000502:physiology
D018756:GABA Antagonists; D018094:Receptors, Metabotropic Glutamate; D002104:Cadmium; D001418:Baclofen