Fig. 2

Repeated NTG administration increased the expression of migraine-related proteins in the TNC, such as c-Fos, p-ERK and CGRP. a Coronal view showing the location of the TNC in the mouse brain, which is the region of interest. b The ratio of the p-ERK immunoreactive area to the total area of the TNC was increased in the group treated with NTG (NTG-9D group). Unpaired t test, ***p < 0.001 versus the saline group (n = 6 mice per group). c Changes in p-ERK immunoreactivity in the TNC after repeated nitroglycerin (NTG) or saline administration for 9 days; × 20 objective lens; scale bar, 20 μm. d Repeated NTG administration increased the mean OD of the CGRP-immunoreactive fibres. Unpaired t test, ***p < 0.001 compared with the saline group (n = 6 mice per group). e Changes in CGRP immunoreactivity in the TNC after repeated NTG or saline administration for 9 days; × 10 objective lens; scale bar, 200 μm. f Quantification of the average number of c-Fos particles showed that repeated NTG administration significantly increased c-Fos expression in the TNC. Unpaired t test, ***p < 0.001 compared with the saline group (n = 6 mice per group). g Change in c-Fos immunoreactivity in the TNC after repeated NTG or saline administration for 9 days; × 20 objective