نقش ماتريكس متالوپروتئيناز 2 در اثر بي دردي زايي ناشي از مهار نيتريك اكسايد سنتاز نوروني در موش صحرايي

Role of matrix metalloproteinase II in the analgesia induced by neuronal nitric oxide inhibition in rat

Introduction: Matrix metalloproteinase 2 (MMP-2) is one of the inflammatory mediators that is involved in the nociceptive processing and its production is regulated by many inflammatory factors such as nitric oxide. We studied the role of MMP-2 in the analgesia induced by an nNOS inhibitor. Methods: Considering that nitric oxide has many roles in pain processing, we studied the CSF levels of MMP-2 after hind paw formalin injection (50 \i\, 2.5%) and neuronal nitric oxide synthase inhibition intrathecally. We also studied the effect of MMP-2 inhibitor on pain behavior and its role in the analgesic effect of neuronal nitric oxide synthase (nNOS) inhibitor. Results: Rats that received an MMP-2 inhibitor (30 raM) showed severe responses to formalin injection. Pain was reduced after nNOS inhibition. Prior to nNOS inhibitor injection, MMP-2 inhibition reduced the analgesic effects of nNOS inhibitor. Immunological studies showed that MMP-2 was increased in rats that received nNOS inhibitor. Conclusion: These data suggest a possible role for MMP-2 in the analgesia induced by nNOS inhibitors.