Modulation of beta-endorphin secretion from mouse pituitary tumor cells by calmodulin inhibitor W7.
The involvement of calmodulin in the secretion of beta-endorphin from the mouse anterior pituitary tumor cell line, AtT-20, was investigated. The calmodulin inhibitor W7 potentiated secretion produced by 8-BrcAMP, and induced a secretory response to arginine vasopressin, which did not elevate beta-endorphin levels when added alone. Release of hormone in response to CRF was not affected. Calmodulin phosphodiesterase inhibitor 8-MeOMeMIX produced a dose-dependent increase in 8-BrcAMP stimulation, suggesting that inhibition of cAMP degradation is the mechanism of enhancement of 8-BrcAMP-induced secretion in the presence of W7.
D000818:Animals; D002147:Calmodulin / Q000037:antagonists & inhibitors*; D002460:Cell Line; D007700:Kinetics; D051379:Mice; D010911:Pituitary Neoplasms / Q000378:metabolism*; D013449:Sulfonamides / Q000494:pharmacology*; D001615:beta-Endorphin / Q000378:metabolism*
D002147:Calmodulin; D013449:Sulfonamides; D001615:beta-Endorphin; C017967:W 7