Changes in hemodynamic parameters in the hindpaw area during PT nerve stimulation. (A) Typical example of temporal profiles of stimulus-induced changes in hemodynamic parameters measured using LDF. Measurements focused on the hindpaw area shown with a white circle (500 μm in diameter) in Figs 2(C) and 2(D). The horizontal bar denotes the stimulus period (4 sec). (B) Changes in hemodynamic parameters as a function of stimulus intensity. Vertical axis denotes percent increases in tissue blood flow (rRBCFlow), red blood cell velocity (rRBCVeloc), and number of red blood cells (rRBCMass) in the hindpaw area measured with LDF. Horizontal axis denotes index of stimulus intensity as a function of stimulus duration (2, 4 or 8 sec) and current intensity (2.5, 5, 7.5 or 10 mA). Other stimulus conditions were pulse duration of 0.5 msec and stimulus frequency of 5 Hz. Each data point represents 36 measurements from 12 rats. Statistical analysis was done using a Bonferroni multiple comparison test, and P < 0.05 was regarded as statistically significant.