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. 1971 Jun;42(2):215–223. doi: 10.1111/j.1476-5381.1971.tb07102.x

Effect of electrical stimulation and high potassium concentrations on the efflux of [14C] glycine from slices of spinal cord

Judy Hopkin, M J Neal
PMCID: PMC1667155  PMID: 4326322

Abstract

1. The effects of electrical stimulation and solutions containing a high concentration of potassium on the efflux of [14C] glycine from slices of rat spinal cord have been studied.

2. Slices of cord were incubated with [14C] glycine which rapidly accumulated in the tissue. The slices were then superfused in a small chamber and the radioactivity released from the tissue was measured. After superfusion for 60 min, 98% of the radioactivity remaining in the tissue was present as unchanged glycine.

3. The spontaneous efflux of [14C] glycine consisted of an initial rapid phase followed by a much slower release of [14C] glycine. After superfusion for 60 min, more than 65% of the radioactivity taken up during the incubation period was retained by the tissue.

4. When the slices were depolarized by electrical stimulation or by solutions containing a high concentration of potassium (40 mM), a striking increase in the efflux of [14C] glycine was produced. This effect was not reduced by the absence of calcium ions in the superfusion medium.

5. Electrical stimulation produced similar increases in the efflux of [3H] GABA and [14C] glutamate from slices of cord but had no significant effects on the efflux of [3H] alanine or [14C] urea.

6. The results are consistent with the suggestion that glycine may be an inhibitory synaptic transmitter substance in the mammalian spinal cord.

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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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