MSI_000001058

Epinephrine, also known as adrenaline, is both a neurotransmitter and a hormone. It plays an important role in your body’s “fight-or-flight” response. It’s also used as a medication to treat many life-threatening conditions. Epinephrine is a catecholamine, a sympathomimetic monoamine derived from the amino acids phenylalanine and tyrosine. It is the active sympathomimetic hormone secreted from the adrenal medulla in most species. It stimulates both the alpha- and beta- adrenergic systems, causes systemic vasoconstriction and gastrointestinal relaxation, stimulates the heart, and dilates bronchi and cerebral vessels. It is used in asthma and cardiac failure and to delay absorption of local anesthetics. Epinephrine also constricts arterioles in the skin and gut while dilating arterioles in leg muscles. It elevates the blood sugar level by increasing hydrolysis of glycogen to glucose in the liver, and at the same time begins the breakdown of lipids in adipocytes. Epinephrine has a suppressive effect on the immune system. [HMDB] Epinephrine, also called adrenaline, is both a hormone and a neurotransmitter. As a hormone, it’s made and released by your adrenal glands, which are hat-shaped glands that sit on top of each kidney. As a central nervous system neurotransmitter, it’s a chemical messenger that helps transmit nerve signals across nerve endings to another nerve cell, muscle cell or gland cell. Epinephrine is part of your sympathetic nervous system, which is part of your body’s emergency response system to danger — the “fight-or-flight” response. Medically, the flight-or-flight response is known as the acute stress response. Epinephrine is also called a catecholamine, as are norepinephrine and dopamine. They’re given this name because of a certain molecule in its structure. As a hormone, epinephrine is made from norepinephrine inside of your adrenal gland. As a neurotransmitter, epinephrine plays a small role. Only a small amount is produced in your nerves. It plays a role in metabolism, attention, focus, panic and excitement. Abnormal levels are linked to sleep disorders, anxiety, hypertension and lowered immunity. Epinephrine’s major action is in its role as a hormone. Epinephrine is released by your adrenal glands in response to stress. This reaction causes a number of changes in your body and is known as the fight-or-flight response.