Antagonists
Vasopressin receptor antagonists (VRAs) are drugs that block vasopressin receptors. Most commonly VRAs are used to treat hyponatremia caused by syndrome of inappropriate antidiuretic hormone secretion (SIADH), congestive heart failure (CHF) and cirrhosis.
Normally, when osmolality falls below its set point, plasma vasopressin levels become undetectable, and an aquaresis results. In SIADH, vasopressin release is not fully suppressed, despite hypotonicity. In cirrhosis and CHF, impaired delivery of solute to the diluting sites or diminished glomerular filtration rate causes impairment of maximal water-excretory capacity, resulting in persistence of vasopressin release leading to water retention.
Vasopressin receptor antagonists include the new class of "vaptan drugs" such as conivaptan, tolvaptan, mozavaptan, lixivaptan, satavaptan etc.
Read more about this topic: Vasopressin Receptor
Famous quotes containing the word antagonists:
“There is a persuasion in the soul of man that he is here for cause, that he was put down in this place by the Creator to do the work for which he inspires him, that thus he is an overmatch for all antagonists that could combine against him.”
—Ralph Waldo Emerson (1803–1882)