Sprague-Dawley rats (n = 3) were anesthetized and IS or CFA was added (see above) and monitored with a photo microscope (Olympus SZX10) at baseline and after 15 min following the addition of the inflammatory substances. For the three rats, parasagittal craniotomy, with a diameter of 6 mm, was performed and analyzed on both the left and right parietal bone.