Question

Circulating levels of vasopressin (AVP) in response to changes in osmolality. Plasma AVP becomes detectable in euvolemic, healthy individuals at a threshold of ~285 mOsm/kg, above which there is a linear relationship between osmolality and circulating AVP. The vasopressin response to osmolality is modulated strongly by volume status. The osmotic threshold is thus slightly lower in hypovolemia, with a steeper response curve; hypervolemia reduces the sensitivity of circulating AVP levels to osmolality.

Answer 1

The circulating levels of vasopressin (AVP) in response to changes in osmolality are influenced by volume status. In euvolemic individuals, plasma AVP becomes detectable at around 285 mOsm/kg, and there is a linear relationship between osmolality and circulating AVP. However, in hypovolemia, the osmotic threshold is slightly lower with a steeper response curve, while hypervolemia reduces the sensitivity of AVP levels to osmolality.