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The adrenal medulla is the body's main source of the catecholamine hormones epinephrine and norepinephrine. By contrast, some cells of the adrenal cortex belong to the hypothalamic-pituitary-adrenal axis and are the source of cortisol synthesis. Other cortical cells produce androgens such as testosterone, while some regulate waterDrinking water This article focuses on water as we experience it every day. The water (molecule) article describes water from a scientific and technical perspective. Water is an abundant substance on Earth. It exists in many forms, such as sea, rain, and and electrolyteAn electrolyte is a substance which dissociates free ions when dissolved (or molten), to produce an electrically conductive medium. Because they generally consist of ions in solution, electrolytes are also known as ionic solutes . They are sometimes refer concentrations by secreting aldosteroneAldosterone is a steroid synthesized in the mid-section of the adrenal cortex of the adrenal gland. It is the sole endogenous member of the class of mineralocorticoids. It helps regulate the body's electrolyte balance by acting on the mineralocorticoid re.
Composed mainly of hormone-producing chromaffin cellChromaffin cells are neuroendocrine cells found in the medulla of the adrenal gland and in other ganglia of the sympathetic nervous system. They are derived from the embryonic neural crest. These cells are so-named because they can be visualized by stainis, the adrenal medulla is the principal site of the conversion of the amino acidIn chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. In biochemistry, this shorter and more general term is frequently used to refer to alpha amino acids: those amino acids in which the amino and carb tyrosineTyrosine (from the Greek tyros for "cheese", where it was first discovered), 4-hydroxyphenylalanine or 2-amino-3(4-hydroxyphenyl)-propanoic acid is one of the 20 amino acids that are used by cells to synthesize proteins. It has a phenol side chain. It pla into the catecholamines epinephrineEpinephrine (also adrenaline epi in medical jargon) is a hormone and acts as a neurotransmitter. Both names mean the same: the Latin roots ad ''renes and the Greek roots epi ''nephros both literally mean "on/to the kidney" (referring to the adrenal gland, and norepinephrine (also called adrenaline and noradrenaline, respectively). Medullary cells are derived from the embryonic neural crest and, as such, are simply modified neurons. In particular, they are postganglionic cells of the sympathetic nervous system, receiving innervation from corresponding preganglionic fibers. Moreover, as the synapses between pre- and postganglionic fibers are called ganglia, the adrenal medulla is actually a ganglion of the sympathetic nervous system.
In response to stressor s such as exercise or imminent danger, medullary cells release catecholamines into the blood in a 70:30 ratio of epinephrine to norepinephrine. Notable effects of epinephrine and norepinephrine include increased heart rate, blood vessel constriction, bronchiole dilation, and increased metabolism, all of which are characteristic of the fight-or-flight response.