Figure 7

Chlorpheniramine, an H1 antagonist, inhibits the scratching response and pERK expression induced by histamine but not DNFB. (A, B) The numbers of scratches (A) and pERK-positive cells in the dorsal horn (B) induced by histamine injection are both significantly reduced after intraperitoneal administration of chlorpheniramine (10 mg/kg). (C, D) The number of scratches (C) and pERK-positive cells (D) induced by repeatedly painting DNFB remain unchanged in mice receiving the same chlorpheniramine treatment. Chlorph, chlorpheniramine. n = 6 for each group. Student’s t-test; *P < 0.05; **P < 0.01.