The Properties of the Uptake System for Glycine in Synaptic Vesicles.
Abstract
The present study provides evidence for the presence of a temperature sensitive and energy dependent uptake mechanism for glycine in synaptic vesicles isolated from rat spinal cord. The in vitro uptake of glycine in synaptic vesicles was driven by an electrochemical proton gradient generated by a Mg2+-ATPase in the vesicle membrane. The properties of the vesicular uptake of glycine in spinal cord were clearly different from those of the plasma membrane uptake of glycine, both with respect to Na+, Mg2+ and ATP dependence and the developmental time course. Surprisingly glycine was also taken up by vesicles from whole brain, including cerebral cortex, and the GAB/glycine uptake ratios in different brain regions and spinal cord were similar and very different from the corresponding synaptosomal uptake ratios. These results indicate that glycine was n up non-glycinergic vesicles, and the finding that glycine and GABA competitively inhibited each others uptake into vesicles from brain and spinal cord, indicates that GABA and glycine may be taken up by the same vesicle population. Uptake of glutamate, GABA and glycine in synaptic vesicles from CNS was shown to increase during development, probably in parallel with synaptogenesis, and this indicates a functional role of uptake of the three amino acids by synaptic vesicles In t re nerve terminals. Amino acid neurotransmitters, Aminosyre nevrotransmittorer, Central Nervous System, Sentralnervesystemet, Synaptic vesicles, Synaptiske vesikler, Vesicular uptake, Vesikulaert opptak, Development, Utvikling.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1992
- Accession Number
- ADA255033
Entities
People
- Hege Christensen
Organizations
- Norwegian Defence Research Establishment