The stimulation by synaptic transmitters of the incorporation of oleate into the phospholipid of synaptic membranes.
Noradrenaline stimulated the incorporation of oleate into choline glycerophospholipids of guinea-pig brain synaptic membranes incubated in sodium phosphate buffer. In the presence of 1 mm-NaF, noradrenaline stimulated the incorporation of oleate into the choline glycerophospholipids, phosphatidylinositol, ethanolamine glycerophospholipids, phosphatidylserine and phosphatidic acid of synaptic membranes incubated in 10 mm-Tris-HCl buffer. In Tris-CHl containing 1 mm-NaF, stimulation of incorporation of oleate into choline glycerophospholipids by noradrenaline was enhanced by ATP, CaCl2, MgCl2 and CoA plus dithiothreitol. The optimum concentration of CaCl2 for stimulation by 10 mum-noradrenaline was 10 mum. In the presence of CaCl2, the optimum concentration of ATP-2MgCl2 was in the range 0.1-1 mm. Acetylcholine, carbamoylcholine, 5-hydroxytryptamine, dopamine, histamine and gamma-aminobutyric acid also stimulated the incorporation of oleate into choline glycerophospholipids of synaptic membranes. Sigmoidal dose-response curves were obtained, similar to those obtained previously for stimulation by the same agonists of the hydrolysis of phosphatidylcholine by phospholipase A2 (Gullis & Rowe, 1975a). The initial rate of transfer of oleate from oleoyl-CoA to choline glycerophospholipid was similar to the initial rate of transfer from oleate-albumin, stimulated by noradrenaline. Transfer of oleate from oleoyl-CoA was not appreciably stimulated by noradrenaline, but was stimulated by ATP and MgCl2.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000418:Albumins; D000818:Animals; D001921:Brain / Q000378:metabolism / Q000648:ultrastructure; D002118:Calcium / Q000494:pharmacology; D003065:Coenzyme A / Q000494:pharmacology; D004229:Dithiothreitol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D018377:Neurotransmitter Agents / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology*; D009829:Oleic Acids / Q000378:metabolism*; D010710:Phosphates / Q000494:pharmacology; D010713:Phosphatidylcholines / Q000378:metabolism; D010740:Phospholipases / Q000378:metabolism; D010743:Phospholipids / Q000096:biosynthesis*; D013268:Stimulation, Chemical; D013570:Synaptic Membranes / Q000378:metabolism*
D000418:Albumins; D018377:Neurotransmitter Agents; D009829:Oleic Acids; D010710:Phosphates; D010713:Phosphatidylcholines; D010743:Phospholipids; D000255:Adenosine Triphosphate; D010740:Phospholipases; D008274:Magnesium; D003065:Coenzyme A; D002118:Calcium; D004229:Dithiothreitol; D009638:Norepinephrine