Figure 4.

Activation of spinal Erk by capsaicin in rat spinal cord slices. Compared with control slices (A), bath application of capsaicin (1 μm for 30 min) increased intensity of pErk immunoreactivity in dorsal horn neurons. B, A high-magnification image of the medial superficial dorsal horn in B is provided (C). Immunostaining of pErk was observed in cell bodies and their proximal dendrites. The Erk activation in superficial dorsal horn was significantly decreased by the NK1 receptor antagonist L-733060 (D, E) or a combination of the three glutamate receptor antagonists (E). *Significant difference compared with application of capsaicin alone; p < 0.05. Scale bar: (in D) A, B, D, 100 μm; (in C) C, 50 μm. Error bars indicate SEM.