The following antibodies were used: GFP (1:500, Life Technologies, A10262 or A11122); Nefh (1:1,000, Aves laboratory, NFH or 1:1,000, Abcam, ab8135); CGRP (1:500, Abcam, ab43873); NeuN (1:500, Millipore, MAB377); PECAM1 (1:100, Abcam, ab28364); PV (1:500, Swant, PV 2); α-bungarotoxin (1:500, Life Technologies, B13423); advillin (1:500, Abcam, ab72210); Tuj1 (1:500, Covance, MMS-435P-250); αSMA–Cy3 (1:200, Sigma, C6198); E-cadherin (1:500, Life Technologies, 13–1900); MUC-1 (1:500, Fisher Scientific, HM1630P0); T1α (1:50, DSHB, 8.1.1); proSP-C (1:300, Millipore, AB3786); ChAT (1:300, Millipore, AB143); Piezo2 (1:1,000)21 (link); IB4-Alexa Fluor568 conjugate (1:200, Life Technologies, I21412).