The Sound of Evolution
Conivaptan
Mechanism of action:
Conivaptan is an arginine vasopressin receptor antagonist. Conivaptan blocks both V1A and V2 receptors. V1A receptors are located in vascular smooth muscle, and blocking them can cause vasodilation and mildly reduce blood pressure. V2 receptors are located on the basolateral membrane of epithelial cells in the renal collecting ducts. When these receptors are blocked by conivaptan, cAMP production decreases, aquaporin-2 (AQP2) is not transported to the cell membrane, water reabsorption decreases, water excretion increases, and serum sodium concentration rises.
Reference(s):
1. Ali F et al. (2007). Conivaptan: a dual vasopressin receptor V1a/V2 antagonist. Cardiovasc Drug Rev.
2. Mao ZL et al. (2009). Pharmacokinetics of conivaptan hydrochloride, a vasopressin V(1A)/V(2)-receptor antagonist, in patients with euvolemic or hypervolemic hyponatremia and with or without congestive heart failure from a prospective, 4-day open-label study. Clin Ther.