Abstract | BACKGROUND: Microglia serve as macrophage-like cells in the central nervous system, and activation of microglial cells in the spinal cord may contribute to ongoing pain following peripheral trauma or nerve injury. Following pronociceptive stimulation, activated microglia exhibit increased expression of the peripheral benzodiazepine receptor (PBR)/translocator protein 18 kDa (TSPO). METHODS: RESULTS: Specific [(3)H] PK11195 binding in dorsal and ventral regions of lumbar spinal cord was increased by ≥70% ipsilateral to SNL. Also, specific [(3)H] PK11195 binding in the ipsilateral (injured) lumbar spinal cord was increased by approximately 25% in MIA-OA. In contrast to the data obtained in these chronic neuropathic and nociceptive pain models, specific [(3)H] PK11195 binding in the ipsilateral (injured) dorsal horn was elevated in only one of six CFA rats. Consistent with increased PBR/TSPO binding measured for SNL and MIA-OA rats, increased anti-OX-42 immunostaining of the cell surface microglial marker CD11b was observed in the ipsilateral spinal cord from these models. CONCLUSIONS: These studies demonstrate that [(3)H] PK11195 binding assays may serve as a marker of spinal microglial activation in experimental models of chronic neuropathic or osteoarthritic pain, which may be translatable to clinical research through novel applications of PBR/TSPO imaging agents.
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Authors | T R Miller, J B Wetter, M F Jarvis, R S Bitner |
Journal | European journal of pain (London, England)
(Eur J Pain)
Vol. 17
Issue 5
Pg. 692-703
(May 2013)
ISSN: 1532-2149 [Electronic] England |
PMID | 23070996
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | © 2012 European Federation of International Association for the Study of Pain Chapters. |
Chemical References |
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Topics |
- Animals
- Autoradiography
- Disease Models, Animal
- Isoquinolines
(pharmacology)
- Male
- Microglia
(drug effects, metabolism)
- Neuralgia
(metabolism)
- Osteoarthritis
(metabolism)
- Pain
(metabolism)
- Pain Measurement
- Rats
- Rats, Sprague-Dawley
- Spinal Cord
(metabolism)
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