Fig. 2
Relationships between hemodynamics and the Tm during trigeminal afferent inputs in the orofacial tissues in the rat. a Illustration of the area in the mandibular including lower lip in a supine rat. b Typical example of the real image and speckle images of the BF in the lower lip at the basal level (rest) and produced by left LN stimulation (LN stim.) for 20 s with a supramaximal voltage (20 V) at 20 Hz using 2-ms pulses. Scale bars represent 3.5 mm. c Changes in BF (a.u.; arbitrary units), vascular conductance (VC; a.u./mmHg) and Tm (°C) in the lower lip extracted from a region of interest (ROI) indicated by the white circles in b, and systemic arterial blood pressure (SABP; mmHg) evoked by LN stimulation (arrow head with dashed line). The white traces indicate the mean VC and Tm at the measuring site. d Mean ± standard error of the mean (SEM) of ∆BF, ∆VC, and ∆Tm in the lower lip (black symbols) and the skin of the dorsum of the foot (gray symbols) evoked by LN stimulation at 20 V and various frequencies (1–20 Hz; n = 6 in each group). The responses evoked by LN stimulation were determined by calculating the difference between the maximum value during the 10 min after stimulation and the baseline value. Statistical significance of the differences from the base value (at a frequency of 1 Hz) was assessed by ANOVA followed by a post-hoc test (Fisher’s PLSD). *P < 0.05, **P < 0.01 vs. base value