Neuropeptides in the sympathetic system: presence, plasticity, modulation, and implications

Ann Neurol. 1994 Jul;36(1):6-13. doi: 10.1002/ana.410360105.


Neuropeptides are ubiquitous in the sympathetic system and modulate transmission at the levels of the intermediolateral cell column, sympathetic ganglia, and neuroeffector junctions. Several neuropeptide-containing pathways from the hypothalamus and medulla modulate excitability of preganglionic neurons. Neuropeptides coexist with norepinephrine or acetylcholine in subpopulations of chemically coded, target-specific sympathetic ganglion neurons. Neuropeptide Y is colocalized in adrenergic vasoconstrictor neurons, whereas vasoactive intestinal polypeptide is colocalized in cholinergic sudomotor neurons. Neuropeptide expression is plastic; during development, neurons that switch from a noradrenergic to a cholinergic phenotype increase expression of vasoactive intestinal polypeptide, somatostatin, and substance P. Preganglionic inputs increase neuropeptide Y and inhibit substance P expression. Sympathetic denervation produces sprouting of sensory fibers containing substance P and calcitonin gene-related peptide in target tissues. Neuropeptides from preganglionic fibers (e.g., enkephalin) and primary afferents (e.g., substance P, vasoactive intestinal polypeptide) modulate transmission in sympathetic ganglia. Neuropeptide Y produces vasoconstriction, prejunctional inhibition of norepinephrine release, and postjunctional potentiation of norepinephrine effects. Plasma neuropeptide Y increases during intense sympathoexcitation, hypertension, and pheochromocytoma. Dystrophic neurites containing neuropeptide Y occur in human sympathetic ganglia during aging, diabetes, and dysautonomia. Sympathetic neuropeptides may thus have important clinical implications.

Publication types

  • Review

MeSH terms

  • Aging / physiology
  • Animals
  • Autonomic Nervous System Diseases / physiopathology
  • Cats
  • Diabetic Neuropathies / physiopathology
  • Ganglia, Sympathetic / chemistry
  • Ganglia, Sympathetic / physiology
  • Humans
  • Hypothalamus / physiology
  • Medulla Oblongata / physiology
  • Neural Pathways / physiology
  • Neuronal Plasticity
  • Neuropeptide Y / physiology
  • Neuropeptides / physiology*
  • Sympathetic Nervous System / physiology*
  • Synaptic Transmission / physiology


  • Neuropeptide Y
  • Neuropeptides