Endothelin-1 stimulates cytosolic phospholipase A2 in Chinese hamster ovary cells stably expressing the human ETA or ETB receptor subtype.
The ability of endothelin-1 (ET-1) to activate cytosolic phospholipase A2 (cPLA2) has been studied in Chinese Hamster ovary (CHO) cells stably expressing either the human ETA (CHO/ETA) or the human ETB (CHO/ETB) receptor subtype. ET-1 dose-dependently increased a dithiothreitol-insensitive cPLA2 activity in both cell types. In CHO/ETA cells, BQ-123, an ETA-selective antagonist, completely blocked ET-1-induced cPLA2 stimulation. In CHO/ETB cells, the ET-1 response was mimicked by 4AlaET-1 which could be blocked partially by PD 145065, a nonselective antagonist of ETA and ETB. As expected, ET-1 stimulated PGE2 synthesis in CHO cells transfected with ET receptors. We conclude that ET-1 can stimulate cPLA2 via both the human ETA and ETB receptor subtype.
Schramek
H
H
Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106.
Wang
Y
Y
Konieczkowski
M
M
Rose
P M
PM
Sedor
J R
JR
Dunn
M J
MJ
D000818:Animals; D015153:Blotting, Western; D016466:CHO Cells; D006224:Cricetinae; D003600:Cytosol / Q000201:enzymology; D015232:Dinoprostone / Q000378:metabolism; D004229:Dithiothreitol / Q000494:pharmacology; D016232:Endothelins / Q000494:pharmacology*; D004789:Enzyme Activation; D006801:Humans; D007700:Kinetics; D010741:Phospholipases A / Q000302:isolation & purification / Q000378:metabolism*; D054467:Phospholipases A2; D017466:Receptors, Endothelin / Q000096:biosynthesis / Q000187:drug effects / Q000502:physiology*; D014162:Transfection
D016232:Endothelins; D017466:Receptors, Endothelin; D010741:Phospholipases A; D054467:Phospholipases A2; D015232:Dinoprostone; D004229:Dithiothreitol