Chemical Anatomy of the Dorsal Horn

Abstract

Catecholamines are highly reactive compounds derived from tyrosine, which proceed via tyrosine hydroxylase (TH) to DOPA, then through DOPA decarboxylase to dopamine (DA), then through dopamine $β$-oxidase (D$β$H) to noradrenaline (NA), and finally through phenylethanolamine N-methyltransferase (PNMT) to adrenaline. These compounds have many biologic functions, for example, neurotransmitters in the sympathetic nervous system, but for spinal sensory functions they are considered in relation to nociceptive transmission.