Endocrine glands
Endocrine glands release (secrete) hormones into the bloodstream.
The endocrine glands include:
- Adrenal
- Hypothalamus
- Islets of Langerhans in the pancreas
- Ovaries
- Parathyroid
- Pineal
- Pituitary
- Testes
- Thyroid
Endocrine glands release hormones (chemical messengers) into the bloodstream to be transported to various organs and tissues throughout the body. For instance, the pancreas secretes insulin, which allows the body to regulate levels of sugar in the blood. The thyroid gets instructions from the pituitary to secrete hormones which determine the rate of metabolism in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Although the thyroid gland releases the hormones which govern growth and metabolism, the brain (the pituitary and the hypothalamus) manages the release and the balance of the amount of hormones circulated.
Information
Hypersecretion is when an excess of one or more hormone is secreted from a gland. Hyposecretion is when the amount of hormones that are released is too low.
There are many types of disorders that can result when too much or too little of a hormone is released.
Disorders that may be associated with abnormal hormone product from a particular gland include:
Adrenal:
- Addison disease
- Adrenogenital syndrome or adrenocortical hyperplasia
- Cushing syndrome
- Pheochromocytoma
Pancreas:
Parathyroid:
- Low blood calcium level
- Tetany (abnormal cramping of muscles)
- Renal calculi (kidney stones)
- Excessive loss of minerals from bone (osteoporosis)
Pituitary:
Testes and ovaries:
- Lack of sex development (unclear genitalia)
Thyroid:
References
Barrett EJ. Organization of endocrine control. In: Boron WF, Boulpaep EL, eds. Medical Physiology. 3rd ed. Philadelphia, PA: Elsevier; 2017:chap 47.
Melmed S, Auchus RJ, Goldfine AB, et al. Principles of endocrinology. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 1.
Newell-Price JDC, Gibb FW. Endocrinology. In: Penman ID, Ralston SH, Strachan MWJ, Hobson RP, eds. Davidson's Principles and Practice of Medicine. 24th ed. Philadelphia, PA: Elsevier; 2023:chap 20.
Version Info
Last reviewed on: 5/12/2023
Reviewed by: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
