Answer:
ADH
Explanation:
The osmotic pressure depends on the osmolality of the plasma. In addition, the plasma osmolality is measured by the plasma content of the total body. And when there is a drop in total body volume then the plasma osmolality will boost as the plasma concentration of Na+ will rise.
As a response, water will transfer the concentration gradient downward from all cells to plasma. It causes contraction of the osmoreceptors cells. As a consequence, afferent impulses are sent to the posterior pituitary gland from the hypothalamus, to enhance the production of ADH.
