Which of the following statements about parathyroid hormone is NOT true?

Parathyroid hormone (PTH) plays a crucial role in regulating calcium levels in the blood, ensuring that calcium homeostasis is maintained. When calcium levels drop, the parathyroid glands release PTH, which acts on several targets in the body to increase calcium levels. This includes enhancing the activity of osteoclasts, which are cells responsible for breaking down bone and releasing calcium into the bloodstream.

PTH is specifically produced in the parathyroid glands, which are small glands located on the back of the thyroid gland. This is central to its function, as any issues with the parathyroid glands can lead to imbalances in calcium levels.

The statement that is not true is that parathyroid hormone is produced in the thyroid gland. This misconception may arise due to the close anatomical relationship between the thyroid and parathyroid glands, but it is essential to understand that they are distinct structures with different functions and regulatory roles in the body. Thus, PTH is exclusively produced in the parathyroid glands, not the thyroid gland.