Substance P release machinery (SNARE complex) (SNARE complex)

The Substance P release machinery in CGRP+ nociceptors refers to the specialized protein assembly, primarily the SNARE complex, responsible for the exocytosis of pro-inflammatory neuropeptides from sensory neurons. This machinery consists of core proteins including SNAP-25, Syntaxin-1, and VAMP-2, which facilitate the fusion of neuropeptide-containing large dense-core vesicles with the presynaptic membrane in response to calcium influx. In CGRP+ (Calcitonin Gene-Related Peptide-positive) nociceptors, the release of Substance P is a critical driver of neurogenic inflammation and pain sensitization. By mediating the secretion of these peptides, the machinery plays a central role in the pathophysiology of chronic pain conditions and migraine. Therapeutic intervention typically involves the use of botulinum neurotoxins, which enzymatically cleave specific components of this machinery to provide long-lasting inhibition of pain signaling and inflammatory mediator release.

Other names

Neuropeptide exocytosis machinerySoluble N-ethylmaleimide-sensitive factor attachment protein receptor complexSNAP-25/Syntaxin-1/VAMP-2 complexSubstance P secretory apparatus

Cleavage of SNARE proteins (SNAP-25, Syntaxin, or VAMP) to prevent the assembly of the fusion complex, thereby inhibiting the calcium-triggered release of Substance P and CGRP from nociceptive terminals.