Arachidonic acid inhibits glycine transport in cultured glial cells.
The effects of arachidonic acid on glycine uptake, exchange and efflux in C6 glioma cells were investigated. Arachidonic acid produced a dose-dependent inhibition of high-affinity glycine uptake. This effect was not due to a simple detergent-like action on membranes, as the inhibition of glycine transport was most pronounced with cis-unsaturated long-chain fatty acids, whereas saturated and trans-unsaturated fatty acids had relatively little or no effect. Endogenous unsaturated non-esterified fatty acids may exert a similar inhibitory effect on the transport of glycine. The mechanism for this inhibitory effect has been examined in a plasma membrane vesicle preparation derived from C6 cells, which avoids metabolic or compartmentation interferences. The results suggest that part of the selective inhibition of glycine transport by arachidonic acid could be due to the effects of the arachidonic acid on the lipid domain surrounding the carrier.
Zafra
F
F
Departamento de Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
Alcantara
R
R
Gomeza
J
J
Aragon
C
C
Gimenez
C
C
D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology*; D001692:Biological Transport / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D004563:Electrochemistry; D005227:Fatty Acids / Q000494:pharmacology; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D005910:Glioma; D005998:Glycine / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D009457:Neuroglia / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013816:Thermodynamics; D014407:Tumor Cells, Cultured; D014634:Valinomycin / Q000494:pharmacology
D001095:Arachidonic Acids; D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D014634:Valinomycin; D012710:Serum Albumin, Bovine; D016718:Arachidonic Acid; D011188:Potassium; D005998:Glycine