MICROANATOMY

Detailed explanation-1: -The parathyroid hormone (PTH), secreted by the parathyroid glands, is responsible for regulating blood calcium levels; it is released whenever blood calcium levels are low. PTH increases blood calcium levels by stimulating osteoclasts, which break down bone to release calcium into the blood stream.

Detailed explanation-2: -Conversely, parathyroid hormone (PTH), released by the parathyroid glands, stimulates osteoclasts. These cells remove calcium from bone and place it into the blood when blood calcium is too low. People naturally have a difficult time maintaining bone calcium and mass with age.

Detailed explanation-3: -Osteoclasts possess the ability to remodel the bones (resorption) by dissolution and degradation of hydroxyapatite and other organic material, releasing calcium into the blood. In the kidneys, the parathyroid hormone has 3 functions in increasing serum calcium levels.

Detailed explanation-4: -Parathyroid hormone regulates calcium levels in the blood, largely by increasing the levels when they are too low. It does this through its actions on the kidneys, bones and intestine: Bones – parathyroid hormone stimulates the release of calcium from large calcium stores in the bones into the bloodstream.