7-Aminoactinomycin D (7-AAD) and TAPI-1 was obtained from Calbiochem (Gibbstown, NJ). cAMP agonist (8-CPT-cAMP) and cAMP antagonist (Rp-8-Br-cAMP) were purchased from BioLog (Bremen, Germany). Phorbol 12-myristate 13-acetate (PMA), ionomycin, monensin, PGE2, forskolin and 3-Isobutyl-1methylxanthine (IBMX), adenosine were obtained from Sigma (St.Louis, MO).