Endocrine gland Endocrine gland Endocrine glands are glands of the endocrine system that secrete their products, hormones, directly into the blood rather than through a duct. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands. The hypothalamus and pituitary gland are neuroendocrine organs. The pituitary gland hangs from the base of the brain by a stalk and is enclosed by bone. It consists of a hormone-producing glandular portion (anterior pituitary) and a neural portion (posterior pituitary), which is an extension of the hypothalamus. The hypothalamus regulates the
Parathyroid gland Hyperparathyroidism is most commonly caused by a benign proliferation of chief cells in single gland, and rarely MEN syndrome. This is known as primary hyperparathyroidism, which is generally managed by surgical removal of the abnormal parathyroid gland. Renal disease may lead to hyperparathyroidism. When too much calcium is lost, there is a compensation by the parathyroid, and parathyroid hormone is released. The glands hypertrophy to synthesise more parathyroid hormone. This is known as secondary hyperparathyroidism. If this situation exists for a prolonged period of time, the parathyroid tissue may become unresponsive to the blood calcium levels, and begin to autonomously