Induction of prostacyclin receptor expression in human erythroleukemia cells.
We have identified both high-affinity (KD = 36 +/- 3 nM) and low-affinity (KD = 2.1 +/- 0.8 microM) prostacyclin (PGI2)-receptor sites on human erythroleukemia (HEL) cells using the radiolabelled prostacyclin analogue. [3H]iloprost. The addition of the phorbol ester, TPA, to the culture medium caused a 5-10-fold increase in the number of both the low- and the high-affinity sites, without any change in their affinity constants. Iloprost stimulated HEL cell membrane adenylate cyclase activity 5-fold. This stimulation was potentiated in the presence of GTP, indicating a conventional PGI2 receptor-G2-adenylate cyclase system. HEL cells represent a source of prostacyclin receptor mRNA which may be of value in expression cloning of this receptor.
Murray
R
R
Division of Clinical Pharmacology, Vanderbilt University, Nashville, TN 37232.
Furci
L
L
FitzGerald
G A
GA
D000262:Adenylyl Cyclases / Q000378:metabolism; D000345:Affinity Labels; D001665:Binding Sites / Q000187:drug effects; D002462:Cell Membrane / Q000201:enzymology; D004790:Enzyme Induction / Q000187:drug effects; D011464:Epoprostenol / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000494:pharmacology; D006801:Humans; D016285:Iloprost; D004915:Leukemia, Erythroblastic, Acute / Q000201:enzymology / Q000378:metabolism*; D010703:Phorbol Esters / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D044006:Receptors, Epoprostenol; D011982:Receptors, Prostaglandin / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000345:Affinity Labels; D010703:Phorbol Esters; D012333:RNA, Messenger; D044006:Receptors, Epoprostenol; D011982:Receptors, Prostaglandin; D006160:Guanosine Triphosphate; D011464:Epoprostenol; D000262:Adenylyl Cyclases; D016285:Iloprost