Paradoxical effect of minocycline on established neuropathic pain in rat

Authors

  • Malek Zarei Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Masoumeh Sabetkasaei Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Taraneh Moini-Zanjani Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

DOI:

https://doi.org/10.17179/excli2016-434

Keywords:

minocycline, neuropathic pain, microglia, allodynia, hyperalgesia, rat

Abstract

Neuropathic pain occurs after peripheral nerve damage, inflammation or infection. In this situation, microglial cells become activated and play a key role in producing pain. Minocycline (microglia inhibitor), was reported to reduce pain when used preventively. However, it seems that, when used after nerve injury, results in its pain reducing effects are different. In this regard, to assess the pain reducing differences of minocycline, neuropathic pain was induced by the ligation of the sciatic nerve in the rat which is recognized as chronic constriction injury (CCI) and minocycline was administered before and after sciatic nerve injury. Wistar male rats (200-250 g, n=6) were used in these experiments. Rats were distributed in various groups: vehicle-treated CCI (control), sham-operated and minocycline-treated CCI groups. In the first part of the experiment (pre-injury study), minocycline (10, 20, 30 and 40 mg/kg,) was injected one hour before surgery and then daily for two weeks. In the second part (post injury study), minocycline was administered: 1: at day one after nerve damage once a day to day 14, 2: at day seven after surgery and continued daily until day 14. Analgesimeter for thermal hyperalgesia and von Frey hairs for mechanical allodynia were used to evaluate pain behavior. Thermal hyperalgesia and mechanical allodynia were attenuated significantly, when minocycline used before surgery, while it was not able to reduce pain behavior administered after surgery. It seems that, in spite of what some previous studies have reported, here, minocycline is not able to attenuate established neuropathic pain.

Downloads

Published

2017-03-08

How to Cite

Zarei, M., Sabetkasaei, M., & Moini-Zanjani, T. (2017). Paradoxical effect of minocycline on established neuropathic pain in rat. EXCLI Journal, 16, 229–235. https://doi.org/10.17179/excli2016-434

Issue

Vol. 16 (2017)

Section

Original articles

License

Authors who publish in this journal agree to the following terms:

  • The authors keep the copyright and grant the journal the right of first publication under the terms of the Creative Commons Attribution license, CC BY 4.0. This licencse permits unrestricted use, distribution and reproduction in any medium, provided that the original work is properly cited.
  • The use of general descriptive names, trade names, trademarks, and so forth in this publication, even if not specifically identified, does not imply that these names are not protected by the relevant laws and regulations.
  • Because the advice and information in this journal are believed to be true and accurate at the time of publication, neither the authors, the editors, nor the publisher accept any legal responsibility for any errors or omissions presented in the publication. The publisher makes no guarantee, express or implied, with respect to the material contained herein.
  • The authors can enter into additional contracts for the non-exclusive distribution of the journal's published version by citing the initial publication in this journal (e.g. publishing in an institutional repository or in a book).