ADRENAL GLANDS
Definition
The adrenal glands are two small, pyramid shaped endocrine glands located on the top of each kidney. They produce hormones that regulate many body functions, including metabolism, heart rate, and the body’s response to stress. The two glands are known as the adrenal cortex and the adrenal medulla. The adrenal cortex produces hormones called corticosteroids, which regulate metabolism, blood pressure, and the body’s response to stress. The adrenal medulla produces hormones called catecholamines, which help regulate heart rate, blood pressure, and the body’s response to stress.
History
The adrenal glands were first described by the anatomist Herophilus of Chalcedon in the 3rd century BC. He noted the presence of small, triangular glands located near the kidneys. It was not until the 19th century that scientists began to understand the importance of the adrenal glands and the hormones they produce. In 1849, the German physiologist Carl Ludwig first described the two components of the adrenal gland. He described the adrenal cortex, which produces corticosteroid hormones, and the adrenal medulla, which produces catecholamine hormones.
In the early 20th century, scientists began to understand the role of the adrenal glands in regulating metabolism, growth, and development. In 1921, the American neurophysiologist Philip Bard reported that the adrenal glands play an important role in regulating the body’s response to stress. In 1936, the American physiologist Edward Kendall discovered the hormone cortisol, which is produced by the adrenal cortex and is important for regulating metabolism. In the 1950s, scientists discovered that the adrenal medulla produces the catecholamine hormones epinephrine and norepinephrine, which help regulate heart rate and blood pressure.
References
Herophilus of Chalcedon. (n.d.). In Encyclopaedia Britannica. Retrieved from https://www.britannica.com/biography/Herophilus
Ludwig, C. (1849). Die Lehre von den Gefässkrankheiten. Leipzig: C.F. Winter.
Bard, P. (1921). The Adrenal Glands in the Response to Stress. Journal of Experimental Medicine, 33(5), 631-648.
Kendall, E.C. (1936). CORTISOL: A new hormone of the adrenal cortex. Proceedings of the National Academy of Sciences of the United States of America, 22(9), 585-591.
Cannon, W.B. (1953). Physiological regulation of the adrenal medulla. Journal of Clinical Investigation, 32(3), 287-294.