摘要：Common chemotherapeutic agents such as oxaliplatin often cause neuropathic pain during cancer treatment in patients. Such neuropathic pain is difficult to treat and responds poorly to common analgesics, which represents a challenging clinical issue. Corydalis yanhusuo is an old traditional Chinese medicine with demonstrated analgesic efficacy in humans. However, the potential analgesic effect of its active component, levo-tetrahydropalmatine ( l -THP), has not been reported in conditions of neuropathic pain. This study found that l -THP (1–4 mg/kg, i.p.) produced a dose-dependent anti-hyperalgesic effect in a mouse model of chemotherapeutic agent oxaliplatin-induced neuropathic pain. In addition, we found that the anti-hyperalgesic effect of l -THP was significantly blocked by a dopamine D1 receptor antagonist SCH23390 (0.02 mg/kg), suggesting a dopamine D1 receptor mechanism. In contrast, l -THP did not significantly alter the general locomotor activity in mice at the dose that produced significant anti-hyperalgesic action. In summary, this study reported that l -THP possesses robust analgesic efficacy in mice with neuropathic pain and may be a useful analgesic in the management of neuropathic pain.
