Inhibitory action of phosphatidylinositol on synaptosomal (Na+ + K+)-ATPase activity.
Phosphatidylinositol and several other phospholipids were tested for their ability to influence the (Na+ + K+)-ATPase activity of the cortical synaptic membrane from rats at various levels of free Ca2+. Phosphatidylinositol, but not phosphatidylethanolamine, phosphatidylcholine nor phosphatidylserine, markedly inhibited this enzyme activity, when the free Ca2+ concentration in the incubation media was less than 2.5 X 10(-6) M. This result suggests that phosphatidylinositol may play a role in the depolarization and/or the release of neurotransmitters or intracellular substances in the brain.
Nishikawa
T
T
Goto
M
M
Shimizu
S
S
D000818:Animals; D001921:Brain / Q000201:enzymology*; D002118:Calcium / Q000378:metabolism; D004533:Egtazic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D010716:Phosphatidylinositols / Q000494:pharmacology*; D010743:Phospholipids / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*; D013574:Synaptosomes / Q000201:enzymology*
D010716:Phosphatidylinositols; D010743:Phospholipids; D004533:Egtazic Acid; D000254:Sodium-Potassium-Exchanging ATPase; D002118:Calcium