Molecular Imaging and Biology

, Volume 13, Issue 1, pp 10–15 | Cite as

Reduced PBR/TSPO Expression After Minocycline Treatment in a Rat Model of Focal Cerebral Ischemia: A PET Study Using [18F]DPA-714

  • Abraham Martín
  • Raphaël Boisgard
  • Michael Kassiou
  • Frédéric Dollé
  • Bertrand Tavitian
Brief Article



Many new candidate pharmaceuticals designed to improve recovery after stroke have been proposed recently, but there are still too few molecular imaging methods capable to assess their efficacy. A hallmark of the inflammatory reaction that follows focal cerebral ischemia is overexpression of the mitochondrial peripheral benzodiazepine receptor/18 kDa translocator protein (PBR/TSPO) in the monocytic lineage and astrocytes. This overexpression can be imaged with positron emission tomography (PET) using PBR/TSPO-selective radioligands such as [18F]DPA-714.


Here, we tested whether PET with [18F]DPA-714 would evidence the effect of minocycline, a broad spectrum antibiotic presently tested as neuroprotective agent after stroke, on the inflammatory reaction induced in an experimental model of stroke.


Ten rats were subjected to a 2-h transient middle cerebral artery occlusion with reperfusion. Minocycline or saline was intravenously administrated 1 h after reperfusion and daily during the following 6 days. PET studies were performed using [18F]DPA-714 at 7 days after cerebral ischemia.


In vivo PET imaging showed a significant decrease in [18F]DPA-714 uptake at 7 days after cerebral ischemia in rats treated with minocycline with respect to saline-treated animals. Minocycline treatment had no effect on the size of the infarcted area.


Minocycline administered daily during 7 days after ischemia decreases [18F]DPA-714 binding, suggesting that the drug exerts an anti-inflammatory activity. [18F]DPA-714 PET is a useful biomarker to study novel anti-inflammatory strategies in experimental cerebral ischemia.

Key words

Minocycline PET Neuroinflammation PBR TSPO DPA-714 Cerebral ischemia 



We thank A. Blossier for technical assistance in the PET studies. This work was funded in part by the EU-FP6 network EMIL (LSHC-CT-2004-503569) and the EU-FP6 network DiMI (LSHB-CT-2005-512146).


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Copyright information

© Academy of Molecular Imaging and Society for Molecular Imaging 2010

Authors and Affiliations

  • Abraham Martín
    • 1
  • Raphaël Boisgard
    • 1
  • Michael Kassiou
    • 2
  • Frédéric Dollé
    • 3
  • Bertrand Tavitian
    • 1
  1. 1.CEA, DSV, I²BM, SHFJ, Laboratoire Imagerie Moléculaire Expérimentale; INSERM U803Orsay CedexFrance
  2. 2.Department of Medical Radiation Sciences and School of ChemistryUniversity of SydneySydneyAustralia
  3. 3.CEA, DSV, I²BM, SHFJOrsayFrance

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