Figure 4

Tissue injury results in the production of kinins and cytokines. Kinins activate both B₁ and B₂ receptors on nerve ending and on other cells (possibly, gingival fibroblasts, epithelial cells or inflammatory cells). The activation of both B₁ and B₂ receptors leads via different signaling pathways to the production of IL-6, IL-8 and CLL2, all of which can activate their corresponding receptors on the sensory nerve endings. Activation of TRPV1 is thought to mediate kinins effects on sensory neurons and might possibly mediate their effect on other cells to produce cytokines.