Osteoporosis is a condition in which the density of bones is decreased so much that the individual is at a higher risk of fractures. The more calcium in the bones, the better the bone density. Which of the following would produce the greatest increase in bone calcium levels?

A) calcitonin injection

B) calcitonin receptor blocker

C) parathyroid hormone injection

D) glucagon receptor blocker

A) Calcitonin injection

Explanation:

Parafollicular cells or C-cells of the thyroid gland produce a hormone which is involved in the regulation of calcium levels in the blood. This hormone is Calcitonin. It works in an antagonistic manner with the Parathyroid hormone (PTH). Calcitonin decreases the calcium level in the blood by increasing absorption of calcium ions in bones. In osteoporosis, when the patient is given the injection of hormone calcitonin, it produces and increase in bone mass because it negatively affects the rate of absorption of bone by the osteoclasts.