A phosphodiesterase (PDE) is an enzyme that catalyzes the hydrolysis of phosphodiester bonds. There are 11 families of PDEs, namely PDE1-PDE11.
PDEs are responsible for the degradation of the cyclic nucleotides cAMP and cGMP. They are therefore important regulators of signal transduction mediated by these molecules.
Inhibitors of PDE can prolong or enhance the effects of physiological processes mediated by these cyclic nucleotides.