Antidiuretic hormone

Antidiuretic hormone (ADH) is also called Vasopressin. It is a naturally occurring hormone that helps in controlling various physical processes and several life-threatening conditions, including bleeding abnormalities and septic shocks. It is mainly involved in regulating and balancing the amount of water in the blood and increasing the glomerular blood flow by increasing the blood pressure. Higher the concentrations of ADH tightens the blood vessels, which increases the blood pressure. The ADH is activated by the posterior portion of the pituitary gland.

The anti-diuretic hormone is secreted by the neurohypophysis of the pituitary gland. Since it stimulates the constriction of blood vessels and results in an increase in blood pressure, therefore it is called vasopressin. The ADH is produced in the hypothalamus, which is stored and secreted by the pituitary gland which lies just beneath the base of the brain.

Read more: Hypothalamus

Functions Of Antidiuretic hormone

The anti-diuretic hormone is involved in the:

1. Regulation of the circadian rhythm.
2. It is mainly responsible for homeostasis.
3. Maintains the proper cellular functions.
4. ADH actively monitors the volume of water in the body and controls it.
5. It acts on the kidneys and the blood vessels and functions to control the blood pressure.
6. It allows the water in the urine to be taken back in a specific area in the kidney and thus, reduces the amount of water excreted through the urine thereby conserving the volume of the fluid in the body.

Regulation of ADH

The release of ADH into the bloodstream is regulated by a number of factors:

1. The decrease in the blood volume or blood pressure is detected by the large blood vessels and the receptors present in the heart stimulate the release of ADH.
2. The increase in the concentration of salts in the bloodstream also controls the secretion of ADH, which is identified by special nerve cells in the hypothalamus.
3. Intake of alcohol also prevents the release of ADH. This causes dehydration and an increase in urine production.
4. If the levels of ADH are higher, the water is retained by the kidney in the body. When excess ADH is released when not required, the blood gets diluted due to excess water retention.
5. The salt concentration in the blood thus decreases. High levels of ADH may be caused due to the side-effects of drugs, lung diseases, etc. Increased ADH is associated with leukaemia, lymphoma, bladder cancer, brain cancer, etc.

Hormones Levels and the Risk Factors of Antidiuretic hormone

The low level of Antidiuretic hormone in the blood cells results in:

1. Diabetes insipidus.
2. Primary polydipsia.
3. Damage to the hypothalamus or pituitary gland.
4. A lot of water is excreted by the kidneys, which increases urine volume and lowers blood pressure.

The higher level of Antidiuretic hormone in the blood cells results in:

1. In acute conditions, the symptoms include – headache, nausea, vomiting, dehydration, etc. In severe cases, coma and seizures can occur.
2. Other symptoms of increased Antidiuretic hormone include- brain cancer, bladder cancer, pancreatic cancer, lung cancer, blood cancer, lymphoma, emphysema, tuberculosis, epilepsy, multiple sclerosis, cystic fibrosis, etc.

Disorders Of ADH

The disorders of the antidiuretic hormone are mainly caused either by a higher or lower level of ADH hormones.

The disorders include:

• Infertility.
• Insomnia.
• Head injuries.
• Delayed puberty.
• Genetic disorders.
• Frequent urination.
• Change in appetite.
• Autoimmune disorders.
• Fluctuations in blood pressure.
• Fluctuations in body temperature.
• Tumours in the hypothalamus or regions near the pituitary gland.

Also Read: Blood Group Test

This article concludes the introduction to the Antidiuretic hormone (ADH), their level of production and functions.

To know more about the Antidiuretic hormone (ADH), other related topics and important questions, keep visiting our website at BYJU’S Biology.