PKC-Dependent Signaling Pathways within PAG and Thalamus Contribute to the Nitric Oxide-Induced Nociceptive Behavior

Figure 1

NO donors decrease the pain threshold without behavioral side effects. Administration of sodium nitroprusside (SNP, 0.5–2 mg/kg i.p.) (a) or nitroglycerin (GTN, 1–10 mg/kg i.p.) (b) induced cold allodynia, evaluated in the cold plate test. ^∗∗∗𝑃<0.001 compared with before administration values. Time course studies showed a prolonged cold allodynia (c, d) and heat hyperalgesia, evaluated in the hot plate test (e, f) that disappeared 6 h after injection. GTN (10 mg/kg) and SNP (1 mg/kg) did not alter motor coordination (rota rod test) (g), spontaneous mobility, and inspection activity (hole board test) (h). ^∗𝑃<0.05,  ^∗∗𝑃<0.01,  ^∗∗∗𝑃<0.001 compared with vehicle-treated mice (VEH).

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