A negative free-water clearance $\left(\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}\right)$ would occur in a person

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[Chapter 5, VII D; Table 5.6]. A person with a negative free-water clearance $\left(\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}\right)$ would, by definition, be producing urine that is hyperosmotic to blood $\left(\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}=\mathrm{V}-\mathrm{C}_{\mathrm{osm}}\right)$. After overnight water restriction, serum osmolarity increases. This increase, via hypothalamic osmoreceptors, stimulates the release of antidiuretic hormone
$(\mathrm{ADH})$ from the posterior lobe of the pituitary. This ADH circulates to the collecting ducts of the kidney and causes reabsorption of water, which results in the production of hyperosmotic urine. Drinking large amounts of water inhibits the secretion of ADH and causes excretion of dilute urine and a positive $\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}$. Lithium causes nephrogenic diabetes insipidus by blocking the response of $\mathrm{ADH}$ on the collecting duct cells, resulting in dilute urine and a positive $\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}$. In option $\mathrm{D}$, the calculated value of $\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}$ is zero. In option $\mathrm{E}$, the calculated value of $\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}$ is positive.

A Negative Free-Water Clearance (CH2O)\left(\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}\right)(CH2​O​) Would Occur in a Person A) Who Drinks

A Negative Free-Water Clearance $\left(\mathrm{C}_{\mathrm{H}_{2} \mathrm{O}}\right)$ Would Occur in a Person
A) Who Drinks