Premium
Uptake of Glycine into Synaptic Vesicles Isolated from Rat Spinal Cord
Author(s) -
Christensen Hege,
Fykse Else M.,
Fonnum Frode
Publication year - 1990
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1990.tb01941.x
Subject(s) - strychnine , glycine , oligomycin , synaptic vesicle , vesicle , biochemistry , chemistry , vesicular transport protein , biophysics , glutamate receptor , nigericin , glycine receptor , amino acid , biology , atpase , membrane , receptor , enzyme
Glycine was taken up by a synaptic vesicle fraction from spinal cord in a Mg‐ATP‐dependent manner. The accumulation of glycine was inhibited by carbonyl cyanide‐ m ‐chlorophenylhydrazone (CCCP) and nigericin, agents known to destroy the proton gradient across the vesicle membrane. Vesicular uptake of glycine was clearly different from synaptosomal uptake, with respect to both the affinity constant and the effect of Na + , ATP, CCCP, and temperature. Oligomycin and strychnine did not inhibit the vesicular uptake, showing that neither mitochondrial H + ‐ATPase nor binding to strychnine‐sensitive glycine receptors was involved. It is suggested that the vesicular uptake of glycine is driven by a proton gradient generated by a Mg 2+ ‐ATPase. A low concentration of Cl ‐ had little effect on the uptake of glycine, whereas the uptake of glutamate in the same experiment was highly stimulated. High concentrations of γ‐amino‐ n ‐butyric acid and β‐alanine inhibited vesicular glycine uptake, but glutamate did not. Accumulation of glycine was found to be fourfold higher in a spinal cord synaptic vesicle fraction than in a vesicle fraction from cerebral cortex.