Contents:
- Medical Video: RENAL PHARMACOLOGY 7:ADH (Anti-diuretics Hormone / Vasopressin ) Agonists and Antagonists
- The role of vasopressin antagonists in the treatment of cardiovascular disease
Medical Video: RENAL PHARMACOLOGY 7:ADH (Anti-diuretics Hormone / Vasopressin ) Agonists and Antagonists
Vasopressin antagonists are drugs that bind to vasopressin receptors (V1A, V1B, and V2) and block the action of vasopressin (antidiuretic hormone, ADH), which is a hormone released by the pituitary gland. Vasopressin causes vasoconstriction and increases water reabsorption from the kidneys.
V1A and V2 receptors are found peripherally and V1A and V1B receptors are found in the central nervous system. V1A receptors regulate blood pressure and V2 receptors have an influence on kidney function.
Vasopressin antagonists are used to treat hyponatremia especially in patients with congenital heart failure.
Vasopressin antagonists have two treatments including conivaptan and tolvaptan.
The role of vasopressin antagonists in the treatment of cardiovascular disease
Vasopressin plays a physiological role in the regulation of blood pressure, fluid volume, and serum osmolality. In heart failure, inadequate vasopressin expenditure can result in excessive fluid retention and hyponatremia. The antagonist vasopressin receptor is a new class of active drugs targeted to inhibit one or more different vasopressin receptors, such as V1A (vasoconstriction), V1B (ACTH release) and V2 receptors (inhibition of water reabsorption in the kidney).
In cardiac decompensation with excess fluid, selective V2 (lixivaptan, satavaptan, and tolvaptan) and selective V1A / V2 receptor inhibitors (conivaptan) have been shown to be better in standard therapy, because it allows faster weight loss and faster symptoms improve (example: lack of dyspnea). Inhibition of free water reabsorption without affecting renal sodium excretion of antagonistic vasopressin receptors allows normalization of serum sodium in controlled euvolemic and hypervolemic hyponatremia.
Vasopressin antagonists are well tolerated and do not have a negative effect on kidney function and serum potassium, unlike diuretics. Heart rate and blood pressure are not affected by vasopressin antagonist receptors. Nevertheless, in addition to the excellent acute clinical effects long-term treatment with tolvaptan did not result in a lack of death rates in heart failure patients after an average of 9.9 months of clinical research.
The effects of vasopressin are implicated with various diseases of water retention and heart disease, including heart failure, hyponatremia, hypertension, kidney disease, syndrome of antidiuretic hormone secretion, cirrhosis, and ocular hypertension. Because vasopressin receptors are found in many different tissues, vasopressin antagonists may be useful in the treatment of disorders such as cerebral ischaemia and stroke, Raynaud's disease, dysmenorrhea, and tocolytic treatment. Selective vasopressin V1B antagonists, discussed about their use in the treatment of emotional and psychological disorders. Vaptan is an antagonistic vasopressin receptor with V1A (relcovaptan) or V2 (tolvaptan, lixivaptan) selective or non-selective activity (conivaptan) which can be useful in some disorders. Vasopressin V1A / V2 non-selective antagonists, conivaptan, is the first vaptan recognized by the FDA for the treatment of euvolemic hyponatremia.
Vasopressin antagonist receptors are a new class of drugs that address the problem of fluid retention, hyponatremia, and kidney dysfunction in heart failure. Increased vasopressin in heart failure can cause myocardial fibrosis, hypertrophy, and vasoconstriction by activating V1A receptors, as well as water retention and hyponatremia by activating V2 receptors. Antagonism of the V1A receptor is also beneficial. In comparison, the antagonism of the V2 receptor results in increased water excretion and sodium concentration. The vasopression antagonist receptor can be seen as the first new class of agents with the dominant aquaretic effect, compared with the effect of natriuretic on diuretics. The predominant action of vasopressin antagonist receptors is water excretion, without other electrolyte reduction and less neurohormonal stimulation compared with diuretics.
Classified as a neurohormonal antagonist, vasopressin antagonist receptors can improve blockages and hyponatremia, and prevent the development of left ventricular dysfunction. Some compounds have been evaluated in late-stage clinical trial programs, and at least one can be used to continue standard medical therapy, combining aquaresis for blockages with neurohormonal antagonism for morbidity and mortality. New patents related to heart failure, hyponatremia, anti-diuretic hormones and vasopressin antagonists have been reviewed.
