Norepinephrine signaling pathway

The norepinephrine signaling pathway, also known as noradrenergic signaling, encompasses all cellular processes initiated by the neurotransmitter/hormone norepinephrine, which acts primarily through binding to G protein-coupled adrenergic receptors—classified into alpha (α) and beta (β) subtypes—on various cell types throughout the body. This system regulates critical physiological functions such as cardiovascular tone, stress responses ("fight-or-flight"), glucose metabolism in muscle tissue,[6] mood regulation,[2] cognitive function,[9] immune modulation,[7] and more. Dysregulation contributes to numerous diseases including hypertension/cardiac disorders,[5] depression/schizophrenia,[2] neuroblastoma/paraganglioma/pheochromocytoma via altered expression/activity of the norepinephrine transporter ([NET], SLC6A2), cancer progression through tumor microenvironment modulation,[7] and Alzheimer’s disease via aberrant tau phosphorylation.[9] Therapeutically relevant interventions target individual proteins within this cascade—notably GPCRs like β_1, β_2, α_1, α_2 adrenoceptors—and transporters such as NET.[3][4][7]

Other names

Noradrenergic signalingNoradrenaline signalingAdrenergic signaling (when including both epinephrine and norepinephrine pathways)

Varies by drug class: Receptor antagonists/agonists modulate GPCR activity at adrenergic receptors; Reuptake inhibitors block NET to increase synaptic NE levels; Indirect agonists promote release/reverse transport of NE from presynaptic terminals