cAMPsignalvejen

cAMPsignalvejen, also known as the cyclic adenosine monophosphate signaling pathway, is a pivotal intracellular signaling mechanism that regulates a wide range of physiological processes. It starts with the activation of cell surface receptors, typically G protein-coupled receptors, which stimulate the enzyme adenylyl cyclase. Adenylyl cyclase catalyzes the conversion of ATP to cAMP, a small messenger molecule. The rise in cytosolic cAMP activates protein kinase A (PKA) by binding to its regulatory subunits, causing their dissociation from the catalytic subunits. Freed catalytic subunits phosphorylate target proteins, altering their activity and leading to cellular responses such as changes in gene expression, metabolism, ion channel conductance, and cell proliferation.

The pathway is terminated by the hydrolysis of cAMP to AMP by phosphodiesterases, which are tightly regulated to control signal duration and intensity. Additionally, cAMP signaling interfaces with other pathways, such as the Ca²⁺ signaling cascade and MAP kinase pathways, creating a complex network that fine-tunes cellular behavior.

cAMPsignalvejen is essential in many organisms, from bacteria to mammals. In humans, it plays critical roles in cardiovascular function, endocrine regulation, and neuronal signaling. Dysregulation of the pathway is implicated in diseases such as heart failure, diabetes, and certain cancers. Because of its central regulatory function, the cAMP signaling pathway is a major target for pharmacological interventions, with drugs such as β-adrenergic agonists, phosphodiesterase inhibitors, and PKA modulators modulating its activity for therapeutic benefit.