Median nerve stimulation induces analgesia via orexin-initiated endocannabinoid disinhibition in the periaqueductal gray

^aGraduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan 40402;
^bChinese Medicine Research Center, China Medical University, Taichung, Taiwan 40402;
^cDepartment of Photonics and Communication Engineering, Asia University, Taichung, Taiwan 41354;
^dDepartment of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan 10051;
^eGraduate Institute of Brain and Mind Sciences, College of Medicine, National Taiwan University, Taipei, Taiwan 10051;
^fFaculty of Pharmaceutical Sciences, UCSI University, 56000 Kuala Lumpur, Malaysia;
^gGraduate Institute of Biomedical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan 110;
^hDepartment of Physiology, College of Medicine, Taipei Medical University, Taipei, Taiwan 110;
ⁱInstitute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan 35053;
^jInstitute for Molecular Psychiatry, University of Bonn, 53113 Bonn, Germany;
^kGill Center for Biomolecular Research, Indiana University, Bloomington, IN 47405;
^lDepartment of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405

Edited by Tomas Hökfelt, Karolinska Institutet, Stockholm, Sweden, and approved September 18, 2018 (received for review May 10, 2018)

Footnotes

Author contributions: Y.-H.C., M.T.L., A.Z., K.M., and L.-C.C. designed research; H.-J.L., M.T.L., Y.-T.W., and Y.-H.L. performed research; M.-S.H. and A.Z. contributed new reagents/analytic tools; Y.-H.C., H.-J.L., M.T.L., L.-L.H., K.M., and L.-C.C. analyzed data; and Y.-H.C., M.T.L., L.-L.H., A.Z., K.M., and L.-C.C. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1807991115/-/DCSupplemental.