The Effect of Cyclic AMP on Heme Synthesis by Rat Bone Marrow Cells in Vitro 1

Summary

Cyclic AMP, db-cAMP, epinephrine, and MIX failed to stimulate heme synthesis in rat marrow cultures at all concentrations tested and in relatively large amounts (10^-3 M) greatly inhibited both base line and Ep-stimulated ⁵⁹Fe incorporation into heme. The inhibition may be nonspecific since identical concentrations of ATP and AMP produce a similar effect. Insulin, which is known to lower cyclic AMP levels, was the only material tested other than Ep that stimulated heme synthesis. The possibility that cAMP mediates the action of Ep is discussed.