AVP is a small nine-amino-acid peptide secreted by the neuro-hypophysis in response to minor increases in plasma osmolality or to comparatively larger reductions in blood volume. There is growing evidence that supports a role of AVP in regulation of blood glucose concentration.
AVP is short-lived in plasma, with a mean half-life of 24 minutes, and this hormone plays a major role in water conservation by increasing the permeability of the collecting duct to water and stimulating urea movements in the kidney which promote more intense water reabsorption in the renal medulla.
Researchers discovered that diabetic rats, in contrast to control rats, have increased hypothalamic vasopressin synthesis due to upregulated chloride transporters and an excitatory response evoked by the neurotransmitter GABA. These findings thus reveal a potential mechanistic explanation for elevated vasopressin concentration in diabetes.
Plasma vasopressin levels are elevated in uncontrolled diabetes mellitus. Furthermore, experimental studies demonstrated increased AVP synthesis, which was thought to be a compensatory response to the elevated AVP secretion.
AVP (arginine vasopressin)
