Adrenal gland
The adrenal glands are named for their location relative to the kidneys. The term "adrenal" comes from "ad-" (Latin, "near") and "renes" (Latin, "kidney"). Similarly, "suprarenal", as termed by Jean Riolan the Younger in 1629, is derived from the Latin "supra" () and "renes" (). The suprarenal nature of the glands was not truly accepted until the 19th century, as anatomists clarified the ductless nature of the glands and their likely secretory role – prior to this, there was some debate as to whether the glands were indeed suprarenal or part of the kidney.
Adrenal gland
Catecholamine release is stimulated by the activation of the sympathetic nervous system. Splanchnic nerves of the sympathetic nervous system innervate the medulla of the adrenal gland. When activated, it evokes the release of catecholamines from the storage granules by stimulating the opening of calcium channels in the cell membrane.