Platelet-activating factor stimulates prostaglandin synthesis in cultured cells.
The effects of platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) on phospholipase activity were studied in aortic smooth muscle cells and renal epithelial cells. When platelet-activating factor was added to cells prelabeled with [3H]arachidonic acid, it induced rapid hydrolysis of phospholipids. Up to 28% of incorporated [3H]arachidonic acid was released into the medium from both aortic and renal cells. A transient rise of diacylglycerol was also seen after the addition of platelet-activating factor to these cells. The accumulation of diacylglycerol and monoacylglycerol was relatively small when compared with the total amount of released free arachidonic acid. The amount of [3H]arachidonic acid released was comparable to the loss of phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine, which indicates that platelet-activating factor stimulates phospholipase A2 and C activity in aortic smooth muscle cells and renal epithelial cells. Platelet-activating factor also enhanced prostaglandin biosynthesis in these cells.
Kawaguchi
H
H
Yasuda
H
H
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D002478:Cells, Cultured; D004075:Diglycerides / Q000378:metabolism; D006868:Hydrolysis; D066298:In Vitro Techniques; D007668:Kidney / Q000166:cytology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology* / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism; D010741:Phospholipases A / Q000378:metabolism; D054467:Phospholipases A2; D010972:Platelet Activating Factor / Q000378:metabolism*; D011453:Prostaglandins / Q000096:biosynthesis*; D051381:Rats; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism
D001095:Arachidonic Acids; D004075:Diglycerides; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010716:Phosphatidylinositols; D010972:Platelet Activating Factor; D011453:Prostaglandins; D016718:Arachidonic Acid; D010741:Phospholipases A; D054467:Phospholipases A2; D010738:Type C Phospholipases