Which of the Following Acts on the Intestine, Requiring Calcitriol

Question

Which of the following acts on the intestine, requiring calcitriol production by the kidneys?
A) growth hormone
B) parathyroid hormone
C) calcitonin
D) calcitriol
E) thyroid hormone

Accepted Answer

Parathyroid hormone (PTH) acts on the intestine indirectly by stimulating the production of calcitriol (active form of vitamin D) in the kidneys, which then increases calcium absorption in the intestine.