GENERAL HISTOLOGY

Detailed explanation-1: -Parathyroid hormone is directly involved in the bones, kidneys, and small intestine. In the bones, PTH stimulates the release of calcium in an indirect process through osteoclasts which ultimately leads to the resorption of the bones.

Detailed explanation-2: -Calcitriol is in a class of medications called vitamin D analogs. It works by helping the body to use more of the calcium found in foods or supplements and regulating the body’s production of parathyroid hormone.

Detailed explanation-3: -It is also known as 1, 25-dihydroxycholecalciferol. It is a hormone which binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the expression of many genes. Calcitriol increases blood calcium (Ca2+) mainly by increasing the uptake of calcium from the intestines.