A Patient Complains of Excessive Urine Output and Constant Thirst

question 17

Multiple Choice

A patient complains of excessive urine output and constant thirst. Laboratory tests show an elevated plasma sodium concentration (151 mEq/L) and elevated plasma osmolality (320 mOsm/L) . The urine osmolality is only 75 mOsm/L. Which of the following could explain the patient's problem?

• A) Defective epithelial sodium channel (ENaC)
• B) Defective ROMK proteins
• C) Defective V₂ receptor proteins
• D) Excessive antidiuretic hormone (ADH) secretion
• E) Defective atrial natriuretic peptide (ANP) secretion

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Definitions:

Counterconditioning

A behavior therapy technique that involves replacing an undesirable response to a stimulus with a more desirable one.

Fear of Dogs

A persistent and intense fear of dogs, often categorized as a specific phobia affecting people.

Higher-order Conditioning

A process in behavioral psychology where a conditioned stimulus is paired with a new neutral stimulus, creating a second (often weaker) conditioned stimulus.

Bright Lights

Intense, vivid artificial or natural light, which can influence mood, circadian rhythms, and can be used in light therapy for seasonal affective disorder.