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. 1972 Nov;69(11):3485–3489. doi: 10.1073/pnas.69.11.3485

Specific Glycine-Accumulating Synaptosomes in the Spinal Cord of Rats

Alberto Arregui 1,2,3,4,5, William J Logan 1,2,3,4,5, James P Bennett 1,2,3,4,5,*, Solomon H Snyder 1,2,3,4,5,†
PMCID: PMC389798  PMID: 4508336

Abstract

Subcellular fractionation of rat spinal cord on continuous sucrose density gradients provides evidence for the existence of a specific synaptosomal fraction (enriched in pinched-off nerve endings) that accumulates glycine selectively by way of a high-affinity transport system. The particles in this fraction sediment to a less-dense portion of sucrose gradients than do particles that accumulate neutral, basic, aromatic, and acidic amino acids. Particles accumulating γ-aminobutyric acid are even less-dense than those storing exogenous glycine. The glycine-specific synaptosomal fraction also exists in the brain stem but not in the cerebral cortex. These findings provide neurochemical support for the suggestion that glycine has a specialized synaptic function, perhaps as neurotransmitter, in mammalian spinal cord.

Keywords: neurotransmitters, glutamate, neutral inhibition, γ-aminobutyric acid

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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