Norepinephrine synthesis pathway

The norepinephrine synthesis pathway encompasses the biochemical conversion of the amino acids phenylalanine and tyrosine to norepinephrine through a series of enzymatic steps. Tyrosine is first converted to L-DOPA by tyrosine hydroxylase (the rate-limiting enzyme), then to dopamine by DOPA decarboxylase, and finally to norepinephrine by dopamine β-hydroxylase inside synaptic vesicles. Norepinephrine acts as a neurotransmitter in the central and peripheral nervous systems and as a hormone from the adrenal medulla, influencing numerous physiological functions including stress response, cardiovascular control, and mood regulation. Therapeutically, drugs target various components of this pathway for conditions such as depression, hypertension, and neuroendocrine tumors[1][4][6][7]. Note: The provided target is not a molecule, receptor, or standard drug target, but a biosynthetic pathway. For drug development or mechanistic studies, individual enzymes or transporters within this pathway (e.g., tyrosine hydroxylase, dopamine β-hydroxylase, VMAT, norepinephrine transporter) should be considered true molecular targets[1][3][6][5].

Other names

Noradrenaline biosynthesis pathwayCatecholamine synthesis pathway

Inhibition of norepinephrine synthesis (e.g., metyrosine blocks tyrosine hydroxylase) - Inhibition of vesicular storage (e.g., reserpine blocks VMAT) - Inhibition of reuptake (e.g., antidepressants block norepinephrine transporter) - Inhibition of degradation (e.g., MAO and COMT inhibitors increase norepinephrine levels)