Calcium

Calcium is stored chiefly in the bones, and is the ion present in the greatest proportion.

Calcium Regulation

Calcium is regulated chiefly by parathyroid hormone (PTH). Low levels of calcium stimulate the release of PTH from the parathyroid gland. The release of PTH stimulates the production of Vitamin D, which then acts to increase calcium. It also directly stimulates bone resorption to release Ca, as well as stimulates the kidney and intestines to increase Ca uptake from food. These sources of calcium increase blood Ca levels.

Physiology