Dopamine:An importantneurotransmitter(messenger)inthebrain.
Dopamineis classified as acatecholamine(a class of molecules that serve as neurotransmitters and hormones). It is a monoamine (a compound containingnitrogenformed from氨by replacement of one or more of thehydrogenatoms byhydrocarbonradicals). Dopamine is aprecursor(forerunner) ofadrenalineand a closely relatedmolecule, noradrenaline. Dopamine is formed by the decarboxylation (removal of a carboxyl group) fromdopa.
Dopa is used in the treatment of Parkinson disease. Parkinsondiseaseis believed to be related to low levels of dopamine in certain parts of the brain. When dopa is taken bymouth, it crosses through theblood-brain barrier. Once it has crossed from the bloodstream into the brain, it is converted to dopamine. The resulting increase in dopamine concentrations in the brain is thought to improvenerveconduction and to assist in lessening the movement disorders in Parkinson disease.
In 1970 theFDA(Food and Drug Administration) approved dopa in the form ofL-Dopa, or levodopa, for use in the US. The drug revolutionized the treatment of Parkinson disease.
