Vasopressin
Greater than 98.0% as determined by by RP-HPLC.
Description
Product Specs
Greater than 98.0% as determined by Reverse Phase High-Performance Liquid Chromatography (RP-HPLC).
Product Science Overview
Vasopressin is produced in the hypothalamus, specifically in the supraoptic and paraventricular nuclei. It is initially synthesized as a larger precursor protein, which is then cleaved to form the active hormone. The hormone is transported down the axons of the hypothalamic neurons to the posterior pituitary gland, where it is stored in vesicles until it is needed .
The release of vasopressin is primarily triggered by an increase in the osmolality of the blood, which is detected by osmoreceptors in the hypothalamus. When the osmolality rises, indicating that the blood is becoming more concentrated, vasopressin is released into the bloodstream. Additionally, vasopressin release can be stimulated by a decrease in blood volume or blood pressure, which is detected by baroreceptors in the cardiovascular system .
Vasopressin exerts its effects by binding to specific receptors located on the cells of target tissues. There are three main types of vasopressin receptors: V1A, V1B, and V2 .
- V1A receptors are found on the smooth muscle cells of blood vessels and mediate vasoconstriction, which helps to increase blood pressure.
- V1B receptors are located in the anterior pituitary gland and are involved in the regulation of adrenocorticotropic hormone (ACTH) release.
- V2 receptors are found in the kidneys, specifically in the collecting ducts, where they promote the reabsorption of water back into the bloodstream, thus reducing urine output and conserving body water .
The primary function of vasopressin is to regulate the body’s water balance by controlling the amount of water reabsorbed by the kidneys. When vasopressin binds to V2 receptors in the kidneys, it triggers a series of events that lead to the insertion of water channels, known as aquaporins, into the membranes of the collecting duct cells. This allows water to be reabsorbed from the urine back into the bloodstream, thereby concentrating the urine and conserving water .
In addition to its antidiuretic effects, vasopressin also plays a role in maintaining blood pressure. By binding to V1A receptors on blood vessels, vasopressin causes vasoconstriction, which increases peripheral resistance and helps to elevate blood pressure. This is particularly important in situations where blood volume is low, such as during dehydration or hemorrhage .
Abnormalities in vasopressin secretion or action can lead to various clinical conditions. For example, diabetes insipidus is a condition characterized by excessive urination and thirst, which can result from a deficiency in vasopressin production (central diabetes insipidus) or a lack of response to vasopressin by the kidneys (nephrogenic diabetes insipidus) .
Conversely, excessive secretion of vasopressin can lead to a condition known as syndrome of inappropriate antidiuretic hormone secretion (SIADH), which is characterized by water retention, hyponatremia (low blood sodium levels), and concentrated urine .
