Antidiuretic

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An antidiuretic is a substance that helps to control fluid balance in an animal's body by reducing urination, [1] opposing diuresis. [2] Its effects are opposite that of a diuretic. The major endogenous antidiuretics are antidiuretic hormone (ADH; also called vasopressin) and oxytocin. Both of those are also used exogenously as medications in people whose bodies need extra help with fluid balance via suppression of diuresis. In addition, there are various other antidiuretic drugs, some molecularly close to ADH or oxytocin and others not. Antidiuretics reduce urine volume, particularly in diabetes insipidus (DI), which is one of their main indications.

Chemical substance matter of constant composition best characterized by the entities (molecules, formula units, atoms) it is composed of

A chemical substance is a form of matter having constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e., without breaking chemical bonds. Chemical substances can be simple substances, chemical compounds, or alloys. Chemical elements may or may not be included in the definition, depending on expert viewpoint.

Fluid balance is an aspect of the homeostasis of organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes in the various body fluids are kept within healthy ranges. The core principle of fluid balance is that the amount of water lost from the body must equal the amount of water taken in; for example, in humans, the output must equal the input. Euvolemia is the state of normal body fluid volume, including blood volume, interstitial fluid volume, and intracellular fluid volume; hypovolemia and hypervolemia are imbalances. Water is necessary for all life on Earth. Humans can survive for 4 to 6 weeks without food but only for a few days without water.

Animal kingdom of motile multicellular eukaryotic heterotrophic organisms

Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from 8.5 millionths of a metre to 33.6 metres (110 ft) and have complex interactions with each other and their environments, forming intricate food webs. The category includes humans, but in colloquial use the term animal often refers only to non-human animals. The study of non-human animals is known as zoology.

Contents

The antidiuretic hormone class includes vasopressin (ADH), argipressin, desmopressin, lypressin, ornipressin, oxytocin, and terlipressin. Miscellaneous others include chlorpropamide and carbamazepine.

Vasopressin protein-coding gene in the species Homo sapiens

Vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, is a hormone synthesized as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travels down the axon of that cell, which terminates in the posterior pituitary, and is released from vesicles into the circulation in response to extracellular fluid hypertonicity (hyperosmolality). AVP has two primary functions. First, it increases the amount of solute-free water reabsorbed back into the circulation from the filtrate in the kidney tubules of the nephrons. Second, AVP constricts arterioles, which increases peripheral vascular resistance and raises arterial blood pressure.

Desmopressin medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue.

Ornipressin chemical compound

Ornipressin is a vasoconstrictor, haemostatic and renal agent.

See also

Related Research Articles

Diabetes insipidus Human disease

Diabetes insipidus (DI) is a condition characterized by large amounts of dilute urine and increased thirst. The amount of urine produced can be nearly 20 liters per day. Reduction of fluid has little effect on the concentration of the urine. Complications may include dehydration or seizures.

Hyponatremia is a low sodium concentration in the blood. It is generally defined as a sodium concentration of less than 135 mmol/L, with severe hyponatremia being below 120 mEq/L. Symptoms can be absent, mild or severe. Mild symptoms include a decreased ability to think, headaches, nausea, and poor balance. Severe symptoms include confusion, seizures, and coma.

Diuresis is increased urination and the physiologic process that produces such an increase. It involves extra urine production in the kidneys as part of the body's homeostatic maintenance of fluid balance.

Collecting duct system

The collecting duct system of the kidney consists of a series of tubules and ducts that physically connect nephrons to a minor calyx or directly to the renal pelvis. The collecting duct system participates in electrolyte and fluid balance through reabsorption and excretion, processes regulated by the hormones aldosterone and vasopressin.

Posterior pituitary posterior lobe of the pituitary gland

The posterior pituitary is the posterior lobe of the pituitary gland which is part of the endocrine system. The posterior pituitary is not glandular as is the anterior pituitary. Instead, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary, and serve as a site for the secretion of neurohypophysial hormones directly into the blood. The hypothalamic–neurohypophyseal system is composed of the hypothalamus, posterior pituitary, and these axonal projections.

Renal physiology

Renal physiology is the study of the physiology of the kidney. This encompasses all functions of the kidney, including maintenance of acid-base balance; regulation of fluid balance; regulation of sodium, potassium, and other electrolytes; clearance of toxins; absorption of glucose, amino acids, and other small molecules; regulation of blood pressure; production of various hormones, such as erythropoietin; and activation of vitamin D.

Supraoptic nucleus

The supraoptic nucleus (SON) is a nucleus of magnocellular neurosecretory cells in the hypothalamus of the mammalian brain. The nucleus is situated at the base of the brain, adjacent to the optic chiasm. In humans, the SON contains about 3,000 neurons.

Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by excessive unsuppressible release of antidiuretic hormone (ADH) either from the posterior pituitary gland, or an abnormal non-pituitary source. Unsuppressed ADH causes an unrelenting increase in solute-free water being returned by the tubules of the kidney to the venous circulation.

Water intoxication Overhydration

Water intoxication, also known as water poisoning,hyperhydration,overhydration, or water toxemia is a potentially fatal disturbance in brain functions that results when the normal balance of electrolytes in the body is pushed outside safe limits by excessive water intake.

An osmotic diuretic is a type of diuretic that inhibits reabsorption of water and sodium (Na). They are pharmacologically inert substances that are given intravenously. They increase the osmolarity of blood and renal filtrate.

Insect diuretic hormones are hormones that regulate water balance through diuretic action.

Nephrogenic diabetes insipidus is a form of diabetes insipidus primarily due to pathology of the kidney. This is in contrast to central/neurogenic diabetes insipidus, which is caused by insufficient levels of antidiuretic hormone. Nephrogenic diabetes insipidus is caused by an improper response of the kidney to ADH, leading to a decrease in the ability of the kidney to concentrate the urine by removing free water.

Neurophysins are carrier proteins which transport the hormones oxytocin and vasopressin to the posterior pituitary from the paraventricular and supraoptic nucleus of the hypothalamus, respectively.

Vasotocin chemical compound

Vasotocin is an oligopeptide homologous to oxytocin and vasopressin found in all non-mammalian vertebrates and possibly in mammals during the fetal stage of development. Arginine vasotocin (AVT), a hormone produced by neurosecretory cells within the posterior pituitary gland (neurohypophysis) of the brain, is a major endocrine regulator of water balance and osmotic homoeostasis and is involved in social and sexual behavior in non-mammalian vertebrates. In mammals, it appears to have biological properties similar to those of oxytocin and vasopressin. It has been found to have effects on the regulation of REM sleep. Evidence for the existence of endogenous vasotocin in mammals is limited and no mammalian gene encoding vasotocin has been confirmed.

An aquaretic is a class of drug that is used to promote aquaresis, the excretion of water without electrolyte loss. Aquaretics are not strictly speaking diuretics, but are sometimes classified as such.

Lixivaptan chemical compound

Lixivaptan (VPA-985) is a phase III pharmaceutical being developed by Cardiokine, Inc., a specialty pharmaceutical company based in Philadelphia, PA, focused on the development of pharmaceuticals for the treatment and prevention of cardiovascular diseases. Lixivaptan is, as of May 2010, in Phase III clinical trials involving patients with hyponatremia, including those with concomitant heart failure. Hyponatremia is an electrolyte disturbance in which the sodium concentration in the serum is lower than normal. Lixivaptan may help some patients eliminate excess fluids while retaining electrolytes.

Diuretic substance that promotes the production of urine

A diuretic is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. There are several categories of diuretics. All diuretics increase the excretion of water from bodies, although each class does so in a distinct way. Alternatively, an antidiuretic, such as vasopressin, is an agent or drug which reduces the excretion of water in urine.

References

  1. Antidiuretic+Agents at the US National Library of Medicine Medical Subject Headings (MeSH)
  2. " antidiuretic " at Dorland's Medical Dictionary