neither 8-bromo-camp ( 8-br-camp ) ( 10 mm ) , cholera toxin ( 10 micrograms/ml ) , nor phosphodiesterase inhibitors [ theophylline , 2 and 8 mm ; 3-isobutyl-1-methylxanthine ( mix ) , 0.2 mm ] had any detectable effect on release of immunoreactive lh ( ir-lh ) when used alone .
C0039771
theophylline
C0000096
3-isobutyl-1-methylxanthine