Serelaxin (Relaxin-2)

A synthetic cyclic heptapeptide modeled after the KGD (Lys-Gly-Asp) disintegrin sequence found in the venom of the southeastern pygmy rattlesnake (Sistrurus miliarius barbouri). Eptifibatide is a potent, reversible glycoprotein IIb/IIIa receptor antagonist that blocks the final common pathway of platelet aggregation by preventing fibrinogen and von Willebrand factor binding to activated platelets.

A recombinant form of human B-type natriuretic peptide (BNP), a 32-amino acid peptide naturally produced by ventricular cardiomyocytes in response to volume overload and wall stress. Nesiritide binds natriuretic peptide receptor A (NPR-A), activating guanylyl cyclase and increasing intracellular cGMP to produce venous, arterial, and coronary vasodilation, natriuresis, and suppression of the renin-angiotensin-aldosterone and sympathetic nervous systems.

A synthetic form of the endogenous octapeptide angiotensin II, the primary effector of the renin-angiotensin system. Angiotensin II acts on AT1 receptors on vascular smooth muscle to produce potent vasoconstriction, and on the adrenal cortex to stimulate aldosterone release. Exogenous administration raises blood pressure in vasodilatory shock refractory to conventional vasopressors by restoring vascular tone through a mechanism complementary to catecholamine vasopressors.

Carperitide is a recombinant form of human atrial natriuretic peptide consisting of 28 amino acids. It activates guanylyl cyclase A receptors, increasing intracellular cyclic GMP to promote vasodilation, natriuresis, and diuresis. The peptide reduces cardiac preload and afterload while inhibiting the renin-angiotensin-aldosterone system, providing therapeutic benefit in acute heart failure.