Rebecca Speltz

Ph.D. 2020

Member of MSTP (MD/PhD) program

PhD Thesis Title:

MMG22: A novel bivalent ligand for the treatment of neuropathic pain.

Current Position:

Anesthesiology Resident, Washington University School of Medicine, St. Louis

Previous Position:

Medical Student, University of Minnesota

Undergraduate Institution and Major:

Hamline, B.S., Biochemistry, 2010

Graduate Advisors:

Description of Graduate Research:

My research centers on the novel bivalent ligand, MMG22, designed by the Portoghese lab to target the putative MOR-mGluR5 heterodimer. I will be using a combination of behavioral, electrophysiological, pharmacological, genetic and molecular techniques to study: 1) the efficacy and potency of MMG22 on a rodent model of peripheral neuropathic pain; 2) the development of tolerance to, and potential abuse liability, of MMG22; and 3) the importance of spinal mGluR5 expression on the development and maintenance of neuropathic pain.

Graduate Level Publications:

  • Uhelski ML, Bruce D, Speltz R, Wilcox G, Simone DA. Topical application of loperamide/oxymorphindole, mu and delta opioid receptor agonists, reduces sensitization of C-fiber nociceptors that possess NaV1.8. Neuroscience. 2020; 446:102-112.
  • Speltz R, Lunzer MM, Shueb S, Akgun E, Reed R, Kalyuzhny A, Portoghese PS, Simone DA. The bivalent ligand, MMG22, reduces neuropathic pain after nerve injury without the side effects of traditional opioids. Pain. 2020;161:2041-2057.
  • Sheub SS, Erb SJ, Lunzer MM, Speltz R, Harding-Rose C, Akgün E, Simone DA, Portoghese PS. Targeting MOR-mGluR5 heteromers reduces bone cancer pain by activating MOR and inhibiting the NMDA receptor. Neuropharmacology. Neuropharmacology. 2019 Jul 1:107690. 
  • Leong ML, Speltz R, Wessendorf M. Effects of chronic constriction injury and spared nerve injury, two models of neuropathic pain, on the numbers of neurons and glia in the rostral ventromedial medulla. Neurosci Lett. 2016 Mar 23;617:82-87.

Graduate Abstracts:

  • Speltz RH, Lunzer MM, Kalyuzhny A, Reed R, Akgün E, Portoghese PS, Simone DA. MMG22 and the temporal dynamics of metabotropic glutamate receptor 5 and μ opioid receptor expression in lumbar dorsal root ganglia after peripheral nerve injury. International Association for the Study of Pain, Boston, MA. 2018.
  • Speltz RH, Lunzer MM, Kalyuzhny A, Reed R, Akgün E, Portoghese PS, Simone DA. MMG22: a bivalent ligand that contains a MOR agonist and an mGluR5 antagonist exhibits potent antinociception without adverse effects. Society for Neuroscience, Washington D.C., 2917

Professional Memberships:

  • Society for Neuroscience

Thesis Committee Members:

Research Categories:

  • Neurobiology of Pain & Somatosensation
  • Neuropharmaceutics
  • Neuroscience of Drug Abuse & Addiction


  • Donald Simone, Ph.D., Department of Diagnostic and Biological Sciences
  • Ann Parr, M.D./Ph.D., Department of Neurosurgery
  • Glenn Giesler, Ph.D., Department of Neuroscience 

Why Did You Choose MN?

I chose Minnesota because of the amazing group of basic pain research faculty here and because of the collaborative nature of the neuroscience program as a whole. 

Rebecca Speltz Paiz