Catecholamines

Dopamine, norepinephrine, and epinephrine are physiologically active molecules known as catecholamines. Catecholamines act both as neurotransmitters and hormones vital to the maintenance of homeostasis through the autonomic nervous system. Physiologic principles of catecholamines have numerous applications within pharmacology. Pheochromocytoma is a catecholamine-producing neoplasm relevant to clinical medicine.
Catecholamine synthesis within the adrenal medulla is controlled by serum concentration of the amino acid tyrosine. Tyrosine undergoes hydroxylation via tyrosine hydroxylase to form DOPA, which then undergoes decarboxylation to dopamine. Dopamine may be secreted into the bloodstream or undergo further hydroxylation to norepinephrine (noradrenaline). Norepinephrine can be secreted into the bloodstream or further modified by a methyltransferase to epinephrine (adrenaline) and then secreted.

Reference:
Paravati S, Rosani A, Warrington SJ. Physiology, Catecholamines. [Updated 2020 Jul 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NB...

Image credit:
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