A patient experiencing severe diarrhea exhibits increased plasma osmolality. Which mechanism explains why antidiuretic hormone (ADH) secretion increases?

💡 Explanation

Increased plasma osmolality stimulates hypothalamic osmoreceptors, because these receptors are sensitive to changes in solute concentration. This triggers ADH release from the posterior pituitary, therefore promoting water reabsorption in the kidneys rather than water loss due to decreased ADH.

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