If a patient develops central diabetes insipidus and fails to produce ADH, why does the collecting duct's ability to concentrate urine significantly decrease?

💡 Explanation

The collecting duct's ability to concentrate urine depends on ADH-mediated aquaporin insertion. Central diabetes insipidus disrupts this process because ADH is absent, therefore aquaporin insertion is reduced, rather than altered sodium reabsorption or aldosterone release causing this urine concentration defect.

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