Figure 6.

CGRP injection dilated dural vessels and decreased voluntary locomotion. A, 2PLSM images of the same region after different drug treatments. Each drug treatment was done on a different day, and images were taken from periods when the mouse was still. Green, red, and blue boxes enclose the measured dural vessel, pial artery, and pial vein, respectively. Dural vessels, but not pial arteries or veins, were dilated substantially after CGRP injection. Sumatriptan blocked the CGRP-induced dilation. B, Vessel diameter changes before and after drug treatments across the time. Vessel diameter was normalized to the preinjection baseline diameter, and only still periods were used. Shaded areas denote SDs. C, Vessel diameter ratio (after drug treatment/baseline) 10–15 min after drug treatments. Only the diameter ratio of dural vessel under CGRP treatment was significantly larger than the saline control group and all other drug combination groups (***p < 0.001, two-way ANOVA and multi-comparison Tukey's test). Data consisted of 46 dural vessels, 33 arteries, and 24 veins from 11 mice. D, Ratio of mouse locomotion before and 10–15 min after drug injection (11 mice). Only CGRP treatment decreased locomotion relative to saline (*p = 0.013, multi-comparison Tukey's test).