Figure 9 - VR1 activation in nerve endings triggers the release of substance P (SP), calcitonin gene-related-peptide (CGRP), and neurokinin A.

This leads to local vasodilation and edema owing to mast cell histamine release and lymphocyte-mediated hypersensitivity reactions. (Source: Szallasi and Blumberg,⁵⁸ with permission from American Society for Pharmacology and Experimental Therapeutics.)