Endothelin-1 is a bicyclic 21 amino acid peptide, produced primarily in the endothelium. It is a potent stimulus of long-lasting and persistent vasoconstriction. It also has a role as a stimulus of inflammation, oxidative stress and cellular proliferation. Proteins on this pathway have targeted assays available via the [CPTAC Assay Portal](https://assays.cancer.gov/available_assays?wp_id=WP2197) adenylate cyclase Prostaglandin I2 Receptor Calponin; tonically inhibits the ATPase activity of myosin in smooth muscle myosine light chain Calmodulin binding protein; tonically inhibits the ATPase activity of myosin in smoothe muscle; mediating factor for Ca²⁺ dependent inhibition of smooth muscle contraction inhibition by phosphorylation and thereby preventing association with CaM Inhibition by phosphorylation stimulation by phosphorylation Inhibition by phosphorylation Sympathic nerve Sensory motor nerve G protein mediated signaling pathway via Galphaq family PW:0000229 Pathway Ontology benign essential hypertension DOID:10913 Disease smooth muscle cell CL:0000192 Cell Type G protein mediated signaling pathway via Galphai family PW:0000228 Pathway Ontology hypertension DOID:10763 Disease G protein mediated signaling pathway via Galphas family PW:0000227 Pathway Ontology calcium/calmodulin dependent signaling pathway PW:0000314 Pathway Ontology Ras superfamily mediated signaling pathway PW:0000006 Pathway Ontology blood vessel endothelial cell CL:0000071 Cell Type endothelin signaling pathway PW:0000506 Pathway Ontology