Aminophylline is a nonselective adenosine receptor antagonist and phosphodiesterase inhibitor. A PDE3 inhibitor is a drug which inhibits the action of the phosphodiesterase enzyme PDE3. G-Protein coupled receptors to activate phosphodiesterase (PDE) which cleaves cGMP into 5'-GMP. Treatment is based on medication, including ACE inhibitors, loop diuretics, and phosphodiesterase inhibitors. This G protein subunit activates a taste phosphodiesterase and decreases cyclic nucleotide levels. PDE3 is sometimes referred to as cGMP-inhibited phosphodiesterase. Crisaborole is a phosphodiesterase-4 inhibitor, mainly acting on phosphodiesterase 4B (PDE4B), which causes inflammation. A phosphodiesterase (PDE) is an enzyme that breaks a phosphodiester bond. Transducin activates phosphodiesterase, which results in the breakdown of cGMP. Its effect as a phosphodiesterase inhibitor is thought to be small. Caffeine, like other xanthines, also acts as a phosphodiesterase inhibitor. Degradation of cyclic di-GMP is affected by proteins with phosphodiesterase activity. CaMKII will also activate phosphodiesterase, which will then hydrolyze cAMP. The protein encoded by this gene functions as a phosphodiesterase. Sphingomyelin phosphodiesterase 1 belongs to the sphingomyelin phosphodiesterase family.