Cam-PDE 1 activation

Human Ca2+/calmodulin-dependent phosphodiesterase PDE1 is activated by the binding of calmodulin in the presence of Ca(2+). PDE1 has three subtypes PDE1A, PDE1B and PDE1C and their role is to hydrolyze both cGMP and cAMP. Their role is to antagonize the increased concentration of the intracellular second messengers determined by the synthetic activity of the adenylate cyclase enzymes thus governing intracellular cAMP dynamics in response to changes in the cytosolic Ca2+ concentration. PDE1 are mainly cytosolic but different isoforms are expressed in different tissues.

人类钙/钙调蛋白依赖性磷酸二酯酶PDE1在钙离子（Ca(2+)）存在的情况下，通过与钙调蛋白的结合而被激活。PDE1包含三种亚型：PDE1A、PDE1B和PDE1C，它们的功能是水解cGMP和cAMP。其作用是对抗由腺苷酸环化酶的合成活性所决定的细胞内第二信使浓度的增加，从而调控细胞内cAMP的动态变化，以应对细胞质中钙离子浓度变化。PDE1主要存在于细胞质中，但不同的同工酶形式在不同的组织中表达。