Multiple choice

Which among the following is excreted in urine?

  1. Calcifediol

  2. Calcipotriol

  3. Calcitriol

  4. Calcitroic acid

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Calcitroic acid (1α-hydroxy-23-carboxy-24,25,26,27-tetranorvitamin D3) is a metabolite of 1α,25-dihydroxyvitamin D3 (calcitriol). Its formation is catalyzed by the enzyme calcitriol 24-hydroxylase. Calcitroic acid is soluble in water and excreted in urine.