ATP-stimulated glutamate-dependent calcium uptake by rat synaptosomes.
The entry of Ca2+ in rat synaptosomes was followed with a Ca(2+)-selective electrode. Extracellular ATP is necessary for the entry which is a function of synaptosomal protein, free Ca2+ and glutamate concentrations. Ketamine, glycine and kainate have negligible effect while quisqualate slightly inhibits the uptake of Ca2+ in the presence of glutamate. The added ATP is hydrolyzed by the synaptosomes through an ouabain-insensitive ecto-ATPase affected by the presence of Ca2+, glutamate and, to a slight extent, NMDA.
Galzigna
L
L
Department of Biological Chemistry, University of Padova, Italy.
Bianchi
M
M
Battistin
T
T
Scarpa
M
M
Rigo
A
A
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002120:Calcium Channel Agonists / Q000494:pharmacology; D005971:Glutamates / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013574:Synaptosomes / Q000378:metabolism*
D002120:Calcium Channel Agonists; D005971:Glutamates; D000255:Adenosine Triphosphate; D002118:Calcium