Expression levels of transient receptor potential vanilloid 1 (TRPV1) in mouse trigeminal ganglion (TG) neurons of C57BL/6 and BALB/c. A: similar levels of Trpv1 mRNA in the TG between C57BL/6 and BALB/c strains (5 animals in each). Data are represented as ratio changes against mean value of C57BL/6. B: immunofluorescence of TRPV1 and isolectin B4 (IB4) in the TG from C57BL/6 and BALB/c strains. Arrows indicate coimmunoreactivity of TRPV1 (red) and IB4 (green). C: coimmunoreactivity of TRPV1 in IB4-positive neurons (V1/IB4; C57BL/6, n = 10/47 and BALB/c, n = 2/48, from 3 animals in each strain) and IB4 binding in TRPV1-immunopositive neurons (IB4/V1; C57BL/6, n = 10/56 and BALB/c, n = 2/48). *P < 0.05, Fisher's exact test.