Guanine nucleotide-binding protein stimulates arachidonic acid metabolism in TEA3A1 thymic epithelial cells by stimulating release and inhibiting incorporation of arachidonic acid.
Guanosine 5'-O-(thiotriphosphate) (GTP gamma S), an activator of guanine nucleotide binding protein (G protein), increased prostaglandin E2 (PGE2) production in saponin permeabilized rat thymic epithelial cells, TEA3A1. Aluminum fluoride (A1F4-), a cell permeable G protein activator, also stimulated PGE2 production and arachidonic acid (AA) release from TEA3A1 cells. Using A1F4- instead of GTP gamma S as a G-protein activator, we have investigated the mechanism of G-protein mediated stimulation of PGE2 production in TEA3A1 cells. Results from our experiments indicate that G protein mediated activation of AA metabolism in TEA3A1 cells is regulated by two independent mechanisms. One is by the stimulation of AA release via the activation of PLA2 enzymatic activity through PLC and PKC mediated pathway and the other is by a concomitant inhibition of AA incorporation into membrane phospholipids.
Liu
P
P
W. Alton Jones Cell Science Center, Lake Placid, NY 12946.
Wen
M
M
Hayashi
J
J
D017607:Aluminum Compounds / Q000494:pharmacology; D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D015153:Blotting, Western; D002460:Cell Line; D004075:Diglycerides / Q000378:metabolism; D015232:Dinoprostone / Q000096:biosynthesis / Q000494:pharmacology; D004847:Epithelial Cells; D005459:Fluorides / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000502:physiology*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D010741:Phospholipases A / Q000378:metabolism; D054467:Phospholipases A2; D010743:Phospholipids / Q000096:biosynthesis; D011493:Protein Kinase C / Q000502:physiology; D051381:Rats; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism*; D010738:Type C Phospholipases / Q000502:physiology
D017607:Aluminum Compounds; D004075:Diglycerides; D010743:Phospholipids; D016718:Arachidonic Acid; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D011493:Protein Kinase C; D010741:Phospholipases A; D054467:Phospholipases A2; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D015232:Dinoprostone; D005459:Fluorides; C032311:aluminum fluoride