Catecholamine

Pronounced cat·e·chol·amine. An amine derived from the amino acid tyrosine — examples include epinephrine (adrenaline), norepinephrine (noradrenaline), and dopamine — that act as hormones or neurotransmitters. There are a number of disorders involving catecholamines, including neuroblastoma, pheochromocytoma, chemodectina, the familial paraganglioma syndrome, dopamine-ß-hydroxalase deficiency, and tetrahydrobiopterin deficiency Neuroblastoma is the second most common solid tumor in childhood (after brain tumors). It usually produce catecholamines. The catecholamine metabolites vanillylmandelic acid and homovanillic acid can be measured quantitatively in the urine as a test for the disease. Pheochromocytoma is a benign tumor derived from the adrenal medulla or sympathetic paraganglia. The tumor secretes epinephrine and norepinephrine. These catecholamines cause attacks of hypertension, headache, nausea and vomiting, sweating, pallor and severe apprehension. Chemodectoma is another benign tumor of the chemoreceptor system, the most common types being the carotid body tumor and the glomus jugulare tumor. Also known as nonchromaffin paraganglioma. Familial paraganglioma syndrome is an unusual familial disease involving slow-growing benign tumors — paragangliomas, glomus tumors, or chemodectomas — predominantly in the head and neck region. The gene for the disease is on chromosome 11q23. The tumors may lead to disfiguring local swellings, cranial nerve injury, or involvement of the base of the skull and may cause dysphonia, aspiration, hearing loss, dysphagia, tinnitus, pain, persistent cough, and shoulder weakness (due to tumor encroachment on cranial nerves). All individuals with hereditary paragangliomas inherit the disease gene from their father. This is consistent with genomic imprinting: the maternally derived gene is inactivated during oogenesis and can be reactivated only during spermatogenesis.

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cat·e·chol·amine .kat-ə-'kō-lə-.mēn, -'kȯ- n any of various amines (as epinephrine, norepinephrine, and dopamine) that contain a dihydroxy benzene ring, that are derived from tyrosine, and that function as hormones or neurotransmitters or both

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cat·e·chol·amine (kat″ə-kolґə-mēn) one of a group of biogenic amines having a sympathomimetic action, the aromatic portion of whose molecule is catechol, and the aliphatic portion an amine; examples are dopamine, norepinephrine, and epinephrine.