Inhibition of gonadotropin-responsive adenylate cyclase in MA-10 Leydig tumor cells by epidermal growth factor.
We have previously shown that mouse epidermal growth factor (mEGF) attenuates the increase in intracellular cAMP provoked by human choriogonadotropin (hCG) in MA-10 Leydig tumor cells (Ascoli, M., Euffa, J., and Segaloff, D. L. (1987) J. Biol. Chem. 262, 9196-9203). The studies presented herein were designed to investigate the mechanism(s) responsible for this phenomenon. We show that mEGF attenuates the increase in cAMP accumulation provoked by hCG primarily, if not entirely, by inhibiting adenylate cyclase activity. This phenomenon has some specificity for the agonist used, but it is not cell-specific. Thus, mEGF inhibited hCG-activated adenylate cyclase in MA-10 cells and in rat luteal cells but had no effect on the forskolin-activated enzyme in MA-10 cells or the isoproterenol-activated enzyme in rat luteal cells.
Pereira
M E
ME
Population Council, New York, New York 10021.
Segaloff
D L
DL
Ascoli
M
M
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000096:biosynthesis; D004789:Enzyme Activation / Q000187:drug effects; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D007984:Leydig Cell Tumor / Q000201:enzymology*; D008184:Luteal Cells / Q000201:enzymology; D051379:Mice; D051381:Rats; D014407:Tumor Cells, Cultured
D000067956:Adenylyl Cyclase Inhibitors; D006063:Chorionic Gonadotropin; D005576:Colforsin; D004815:Epidermal Growth Factor; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D007545:Isoproterenol; D015056:1-Methyl-3-isobutylxanthine