Send to

Choose Destination
Sci Rep. 2016 Dec 2;6:37850. doi: 10.1038/srep37850.

Antinociceptive Profile of Levo-tetrahydropalmatine in Acute and Chronic Pain Mice Models: Role of spinal sigma-1 receptor.

Author information

Department of Physiology and Medical Science, College of Medicine and Brain Research Institute, Chungnam National University, Daejeon 35015, South Korea.
KM Fundamental Research Division Korea Institute of Oriental Medicine, Daejeon 34054, South Korea.
Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, South Korea.
Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555-0625, USA.


We have recently reported that repeated systemic treatments of extract from Corydalis yanhusuo alleviate neuropathic pain and levo-tetrahydropalmatine (l-THP) is one of active components from Corydalis. We designed this study to investigate antinociceptive effect of l-THP in acute and chronic pain models and related mechanism within the spinal cord. We found that intraperitoneal pretreatment with l-THP significantly inhibited the second phase of formalin-induced pain behavior. In addition, intrathecal as well as intraperitoneal pretreatment with l-THP reduced the mechanical allodynia (MA) induced by direct activation of sigma-1 receptor (Sig-1). In chronic constriction injury mice, these treatments remarkably suppressed the increase in MA and spinal phosphorylation of the NMDA receptor NR1 subunit expression on day 7 after surgery. Intrathecal treatment with l-THP combined with the Sig-1R antagonist, BD1047 synergistically blocked MA suggesting that l-THP modulates spinal Sig-1R activation. CatWalk gait analysis also supported that antinociceptive effect of l-THP as demonstrated by restoration of percentages of print area and single stance. Meanwhile, intrathecal pretreatment with naloxone, non-selective opioid receptor antagonist, did not affect the effect of l-THP. In conclusion, these results demonstrate that l-THP possesses antinociceptive effects through spinal Sig-1R mechanism and may be a useful analgesic in the management of neuropathic pain.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center