Fig. 4

c-Fos activation map of brain stem structures in the NTG-induced chronic migraine model. A. Representative pictures of c-Fos (red) and NeuN (green) immunofluorescence labeling in the vlPAG. Scale bars =100 μm. B-C. In vlPAG, no significant differences in c-Fos⁺ cell density (B) and the percentage of c-Fos⁺ cells in NeuN cells (C) were found, alleviated by OLC, n = 5/group. D. Representative pictures of c-Fos (red) and NeuN (green) immunofluorescence labeling in the Sp5c. Scale bars =50 μm. E–F. Sp5c showed a significant increase of c-Fos⁺ cell density (E) and the percentage of c-Fos⁺ cells in NeuN⁺ cells (F). alleviated by OLC, n = 5/group. One-way ANOVA with the Tukey post hoc tests, * P < 0.05, **P < 0.01. Abbreviations: vlPAG, ventrolateral periaqueductal gray; OLC, olcegepant; Sp5c, caudal part of the spinal trigeminal nucleus