Stimulation of Type III Nrg1 signaling enhances response to capsaicin in WT sensory axons.

<p>(A) Representative traces of intracellular calcium along WT sensory axons in response to repeated applications of 1 µM capsaicin followed by application of 56 mM KCl. The maximum percent change in intracellular calcium ([(F−F₀)/F₀]*100) in response to capsaicin decreased between the 4^th and 5^th capsaicin applications under control conditions (left), but increased when Type III Nrg1 signaling was stimulated by sErbB4-ECD application during that interval (right). (B) Quantification of percent change in maximum response to capsaicin between the 4^th and the 5^th capsaicin application ([(F₅−F₄)/F₄]*100) by treatment. WT sensory axons showed a significantly enhanced response to capsaicin when Type III Nrg1 signaling was stimulated with sErbB4-ECD (WT CON, n = 10 animals; WT B4, n = 7 animals; Student's t-test, ***p<0.001). Graph shows mean±SEM.