Supplementary Figure 1: The average sigmoid parametric curves of capillary dilation time courses and average time to 50% peak capillary diameter dilation computed from individual capillary responses averaged per animal in control Pdgfrb^+/+ mice (top, red traces, n = 12 mice, 37 individual capillaries) and pericyte-deficient Pdgfrb^+/− mice (bottom, blue traces, n = 9 mice, 33 individual capillaries).

The time to 50% peak dilation corresponds to the time at which the sigmoid curve reaches 50% of its maximal value, as illustrated by the intercepts of the horizontal dashed line at 0.5 on the ordinate with the curves (diameter increase) and the vertical dashed line intercepts with the abscissa (time to 50% peak dilation). Arrows below the abscissa illustrate time intercepts showing 50% peak capillary diameter dilation per mouse in each group. As in Fig. 1c, diameter changes are expressed relative to the respective basal capillary diameter prior to stimulation (value set as 0) and maximal diameter after stimulation (value set as 1). The average sigmoid curves were derived from individual sigmoid curves fitted to individual capillary responses per animal. The sigmoid fits for individual capillary responses with their intercepts with the horizontal dashed line at 0.5 on the ordinate (diameter increase) and the vertical dashed line intercepts (time to 50% peak dilation) with the abscissa are not shown because of the high degree of overlap, which makes difficult to distinguish responses between individual capillaries. However, data (circles) in Fig. 1d were derived from averaging the individual capillary responses per mouse (time to 50% peak dilation) from sigmoid fits of individual vessel dilation time courses per animal, and then the individual times for 50% peak dilation values were averaged per animal.