Klabunde Vasopressin arginine vasopressin, AVP; antidiuretic hormone, ADH is a peptide hormone formed in the hypothalamus , then transported via axons to the posterior pituitary, which releases it into the blood. There are several mechanisms regulating the release of AVP, the most important of which are the following:. Heart failure is associated with what might be viewed as a paradoxical increase in AVP.
Increased blood volume and atrial pressure associated with heart failure should decrease AVP secretion, but it does not. Alcohol prevents anti-diuretic hormone release, which causes an increase in urine production and dehydration. High levels of anti-diuretic hormone cause the kidneys to retain water in the body. There is a condition called Syndrome of Inappropriate Anti-Diuretic Hormone secretion SIADH; a type of hyponatraemia where excess anti-diuretic hormone is released when it is not needed see the article on hyponatraemia for more information.
With this condition, excessive water retention dilutes the blood, giving a characteristically low salt concentration. Excessive levels of anti-diuretic hormone might be caused by drug side-effects and diseases of the lungs, chest wall, hypothalamus or pituitary. Some tumours particularly lung cancer , can produce anti-diuretic hormone. Low levels of anti-diuretic hormone will cause the kidneys to excrete too much water. Urine volume will increase leading to dehydration and a fall in blood pressure.
Low levels of anti-diuretic hormone may indicate damage to the hypothalamus or pituitary gland, or primary polydipsia compulsive or excessive water drinking. In primary polydipsia, the low level of anti-diuretic hormone represents an effort by the body to get rid of excess water to stop the blood becoming too dilute. Diabetes insipidus is a condition where you either make too little anti-diuretic hormone usually due to a tumour, trauma or inflammation of the pituitary or hypothalamus , or where the kidneys are insensitive to it.
Diabetes insipidus is associated with increased thirst and the production of large amounts to pale urine which can lead to rapid dehydration if untreated.
About Contact Events News. Search Search. Vasopressin also called antidiuretic hormone plays a role in regulating the circadian rhythm — the periods of sleepiness and wakefulness in a hour cycle. Vasopressin also helps maintain the body's internal temperature, its blood volume, and the proper flow of urine from the kidneys.
Both men and women naturally produce vasopressin, yet men experience its effects more strongly because of how it interacts with the male sex hormone testosterone. Nerve cells at the base of the brain hypothalamus make and transport vasopressin to the pituitary gland , which then releases the hormone into the blood stream. Pain, stress, and certain drugs — such as opiates narcotics — can trigger the release of vasopressin.
A condition called syndrome of inappropriate antidiuretic hormone secretion SIADH can occur when the body produces too much vasopressin. If you don't have enough vasopressin, your kidneys may excrete too much water. This causes frequent urination and can lead to dehydration , as well as low blood pressure.
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