Vasopressin

Vasopressin is a peptide and is also known as antidiuretic hormone (ADH), adiuretin, vasopressin (INN) or arginine vasopressin (AVP).

It is closely related to oxytocin and, like oxytocin, is produced in the hypothalamus (1st stage of the HPA axis) and stored in the pituitary gland (2nd stage of the HPA axis) until it is released.

• 1. Formation of vasopressin
• 2. Inhibition of vasopressin
• 3. Degradation of vasopressin
• 4. Effect of vasopressin

1. Formation of vasopressin¶

Vasopressin formation is stimulated by

• Increase in the osmotic concentration of body fluids
• Lack of volume of body fluids
• Drop in blood pressure
• Load
  • Stress¹
  • Trauma
  • Pain
  • Nausea
  • Intense stimuli
    • Olfactory
    • Visual
    • Auditory
  • Intensive orthostatic load
    • Especially presyncopal (in case of impending orthostatic collapse²

Increase rapidly to well over ten times the control value.

2. Inhibition of vasopressin¶

Vasopressin formation is inhibited by

• Signals from cardiovascular baroreceptors (tonic inhibition)
  • Increase in blood pressure inhibits, decrease in blood pressure promotes vasopressin synthesis (disinhibition)
• Atriopeptin
• Alcohol

3. Degradation of vasopressin¶

• Short half-life of 2 - 5 minutes
• Degradation primarily in the liver and kidneys

4. Effect of vasopressin¶

• Vasopressin reduces water excretion in the kidneys via V2 receptors
• High vasopressin concentration acts via V1 receptors
  • Vasoconstrictor (vasoconstrictor)
  • Increases blood pressure
• Vasopressin is part of a stress axis
  • Works together with classic stress hormones such as adrenaline or cortisol.

Vasopressin activates the adrenal gland, unlike oxytocin.
Vasopressin synergistically causes the release of ACTH together with CRH.³
Vasopressin is released more strongly in men than in women (particularly from the paraventricular nucleus (PVN) and the supraoptic cells of the hypothalamus), while oxytocin is released more strongly in women than in men. ⁴
While oestrogen and progesterone probably influence the release of oxytocin in women, this does not appear to be the case with vasopressin.⁴
Vasopressin mediates anxiety. A selective vasopressin V1b receptor antagonist has anxiolytic and antidepressant effects.⁵

Vasopressin correlates positively with

• Aggressiveness (vasopressin in the cerebrospinal fluid and hostile behavior towards other people)
• Learning and memory (positive correlation)

Vasopressin increases the availability of magnesium in the cells.

Vasopressin stimulates the proliferation of osteoblasts and cartilage cells in the growth plates and thus promotes bone formation.
Rats with a mutation of the vasopressin gene, which causes a massive vasopressin deficiency, showed a behavior characterized by hypoarousal and increased thirst. Artificial vasopressin elevation in the magnocellular cells and in their projection to the PVN (paraventricular nucleus of the hypothalamus) reduced thirst but did not alter hypoarousal behavior, which is presumably caused by vasopressin deficiency in other brain regions.⁶