Up-regulation of P2X7 Receptors Contributes to Spinal Microglial Activation and the Development of Pain Induced by BmK-I

  • Jingjing Zhou
  • Xiaoxue Zhang
  • You Zhou
  • Bin Wu
  • Zhi-Yong TanEmail author
Original Article


Previous work has demonstrated that the sensitization of spinal neurons and microglia is important in the development of pain behaviors induced by BmK I, a Na+ channel activator and a major peptide component of the venom of the scorpion Buthus martensi Karsch (BmK). We found that the expression of P2X7 receptors (P2X7Rs) was up-regulated in the ipsilateral spinal dorsal horn after BmK I injection in rats. P2X7R was selectively localized in microglia but not astrocytes or neurons. Similarly, interleukin 1β (IL-1β) was selectively up-regulated in microglia in the spinal dorsal horn after BmK I injection. Intrathecal injection of P2X7R antagonists largely reduced BmK I-induced spontaneous and evoked pain behaviors, and the up-regulation of P2X7R and IL-1β in the spinal cord. These data suggested that the up-regulation of P2X7Rs mediates microglial activation in the spinal dorsal horn, and therefore contributes to the development of BmK I-induced pain.


P2X7 receptor BmK I Spinal dorsal horn Interleukin 1β Microglia Brilliant Blue G 



This work was supported by grants from the National Natural Science Foundation of China (31571032 and 31771191). Zhi-Yong Tan was supported by an Indiana Spinal Cord and Brain Injury Research Fund grant from Indiana State Department of Health, USA (2017).


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Copyright information

© Shanghai Institutes for Biological Sciences, CAS 2019

Authors and Affiliations

  1. 1.Laboratory of Neuropharmacology and NeurotoxicologyShanghai UniversityShanghaiChina
  2. 2.Department of Pharmacology and Toxicology and Stark Neurosciences Research InstituteIndiana University School of MedicineIndianapolisUSA

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