L(-)-Epinephrine

Usage and Decription Epinephrine, is a sympathomimetic hormone secreted by the adrenal medulla and a neurotransmitter, a chemical released by a neuron at a synapse and acts as a electrical signal between a neuron and another cell.

Epinephrine acts to stimulates both the alpha- and beta- adrenergic systems and increase blood pressure due to stimulation of heart action and constriction of peripheral blood vessels. It causes systemic vasoconstriction and gastrointestinal relaxation, and dilates bronchi and cerebral vessels.

The synthetic Levo- form, usually used in the bitartrate salt, is used as a vasoconstricting adjunct to local or regional anesthesia, as a cardiac stimulant, vasopressor; as a systemic antiallergic. It is used in asthma and cardiac failure and to delay absorption of local anesthetics.

Tyrosine, phenolic alpha amino acid, is a precursor of the hormones such as epinephrine, norepinephrine, thyroxine, and triiodothyronine. Dopamine, a catecholamine neurotransmitter as a major transmitter in the extrapyramidal system in the brain, is an intermediate in epinephrine and norepinephrine biosynthesis.

Metanephrineexcreted in the urine is an inactive metabolite of epinephrine. Metanephrine is measured as a test for pheochromocytoma. Norepinephrine is the precursor of epinephrine. It is a major neurotransmitter that acts on both alpha- and beta-adrenergic receptors.

It is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus.

The synthetic bitartrate salt of the Levo- norepinephrine is used as a vasoconstrictor and to restore the blood pressure in certain cases of acute hypotension, and to improve cardiac function during decompensation associated with congestive heart failure or cardiovascular surgery, administered intravenously.