Dataset Information

Segregated Glycine-Glutamate Co-transmission from vGluT3 Amacrine Cells to Contrast-Suppressed and Contrast-Enhanced Retinal Circuits.

ABSTRACT: Since the introduction of Dale's principle of "one neuron releases one transmitter at all its synapses," a growing number of exceptions to this principle have been identified. While the concept of neurotransmitter co-release by a single neuron is now well accepted, the specific synaptic circuitry and functional advantage of co-neurotransmission remain poorly understood in general. Here we report Ca(2+)-dependent co-release of a new combination of inhibitory and excitatory neurotransmitters, namely, glycine and glutamate, by the vGluT3-expressing amacrine cell (GAC) in the mouse retina. GACs selectively make glycinergic synapses with uniformity detectors (UDs) and provide a major inhibitory drive that underlies the suppressed-by-contrast trigger feature of UDs. Meanwhile, GACs release glutamate to excite OFF alpha ganglion cells and a few other nonlinear, contrast-sensitive ganglion cells. This coordinated inhibition and excitation of two separate neuronal circuits by a single interneuron suggests a unique advantage in differential detection of visual field uniformity and contrast.

SUBMITTER: Lee S

PROVIDER: S-EPMC4824647 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Publications

Segregated Glycine-Glutamate Co-transmission from vGluT3 Amacrine Cells to Contrast-Suppressed and Contrast-Enhanced Retinal Circuits.

Lee Seunghoon S Zhang Yi Y Chen Minggang M Zhou Z Jimmy ZJ

Neuron 20160317 1

Since the introduction of Dale's principle of "one neuron releases one transmitter at all its synapses," a growing number of exceptions to this principle have been identified. While the concept of neurotransmitter co-release by a single neuron is now well accepted, the specific synaptic circuitry and functional advantage of co-neurotransmission remain poorly understood in general. Here we report Ca(2+)-dependent co-release of a new combination of inhibitory and excitatory neurotransmitters, name ...[more]

PMID: 26996083

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Dataset Information

Segregated Glycine-Glutamate Co-transmission from vGluT3 Amacrine Cells to Contrast-Suppressed and Contrast-Enhanced Retinal Circuits.

Publications

Segregated Glycine-Glutamate Co-transmission from vGluT3 Amacrine Cells to Contrast-Suppressed and Contrast-Enhanced Retinal Circuits.

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