The clinical specialty of endocrinology focuses on the endocrine organs, i.e. the organs whose primary function is hormone secretion.

   Hormones are chemicals that are manufactured in certain organs of the body and travel through the bloodstream with the purpose of maintaining and regulating the growth and activity of other organs and the body as a whole. In fact, there is not one aspect of human growth and development that is not affected by hormones.

Endocrine Organs include the:
Adrenal glands: these two small glands are located on top of each kidney. The adrenal glands consist of two parts each of which secretes a different hormone. The adrenal cortex secretes steroidal hormones which influence the metabolism of carbohydrates, fats and proteins; maintain normal blood
pressure; and have an anti-inflammatory effect during times of stress. They also secrete sex hormones necessary for the growth of secondary sex characteristics in males and females. The adrenal medulla secretes non-steroidal hormones that play an important role in the body’s response to stress. They increase heart rate, dilate the bronchioles, raise glucose levels of the blood and raise blood pressure.
Pancreas: located in the upper left part of the abdomen, the pancreas produces hormones (including insulin) which is responsible for regulating the amount of glucose in the blood.
Pituitary Gland: a pea sized structure located at the base of the brain. This “Master Gland” has an effect on nearly all body functions.
Thyroid gland: located in the neck & attached to the trachea, the thyroid regulates growth, controls body temp & metabolism. It also regulates the amount of calcium in the blood.
Parathyroid glands: four round tissues on the back of the thyroid gland. Together with the thyroid they help regulate the amount of calcium in the blood.
Thymus gland: primarily responsible for the development of the immune system.
Pineal gland: Pinecone shaped gland located in the midbrain secretes a hormone, melatonin, that seems to have a role in promoting sleep.
Ovaries: Produce the hormones Estrogen & Progesterone which are responsible for the maturation of the egg, preparing the uterus for implantation of a fertilized egg and the growth and development of the placenta. Estrogen is also necessary for the development of secondary female characteristics.
Testes: male sex glands produce testosterone, the hormone responsible for the maturation of sperm and the development of male secondary sex characteristics.

The skin, intestines, heart, and many other organs have some endocrine functions as well.

With such a wide range of endocrine organs it should come as no surprise that there are a wide range of endocrine disorders and each can vary significantly in terms of severity. Following is a brief list of endocrine disorders.

Adrenal disorders:
Adrenal insufficiency
Addison's disease
Congenital adrenal hyperplasia (adrenogenital syndrome)
Mineralocorticoid deficiency
Conn's syndrome
Cushing's syndrome
Pheochromocytoma
Adrenocortical carcinoma
Glucose homeostasis disorders:
Diabetes mellitus
Hypoglycemia
Idiopathic hypoglycemia
Insulinoma
Metabolic bone disease:
Osteoporosis
Osteitis deformans (Paget's disease of bone)
Rickets and osteomalacia
Pituitary gland disorders:
Diabetes insipidus
Hypopituitarism (or Panhypopituitarism)
Pituitary tumors

What is Endocrinology?