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In vivo imaging of microglial activation using a peripheral benzodiazepine receptor ligand: [11C]PK-11195 and animal PET following ethanol injury in rat striatum

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Abstract

Objective

To investigate whether [11C]PK-11195, a specific peripheral benzodiazepine receptors (PBRs) ligand for positron emission tomography (PET), can show activated microglia in a rat brain injury model.

Methods

On day 1, ethanol was injected into the rat’s right striatum (ST) using a stereotaxic operative procedure. On day 3, head magnetic resonance imaging (MRI) scans for surgically treated rats were performed to evaluate ethanol injury morphologically. On day 4, dynamic PET scans (17 injured rats and 7 non-injured controls) were performed for 60 min with an animal PET scanner under chloral hydrate anesthesia following a bolus injection of [11C]PK-11195 through tail vein. Because PBRs are present throughout the brain, there is no suitable receptor-free reference region. The reference tissue model may not be applicable because of low target to background ratio for low affinity of [11C]PK-11195 to PBRs. We evaluated the PBRs binding with regions of interest (ROIs)-based approach to estimate total distribution volume (V). We used an integral from 0 min to 60 min (V 60) as an estimate of V. On the coronal PET image, ROIs were placed on bilateral ST. Differences in right/left ST V 60 ratios between lesioned and unlesioned control rats were compared using unpaired t tests. Immunohistochemical staining was performed for confirming the presence of activated microglia following decapitation on the PET experiment day.

Results

The right/left ST V 60 ratios in lesioned rats (1.07 ± 0.08) were significantly higher than those in unlesioned control rats (1.00 ± 0.06, P < 0.05). On immunohistochemical staining, activated microglia were exclusively observed in the injured right ST but not in the noninjured left ST of the injury rats and the bilateral ST of the non-injured control rats.

Conclusions

These results suggest that [11C]PK-11195 PET imaging would be a useful tool for evaluating microglial activation in a rat brain injury model.

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References

  1. Banati RB. Visualizing microglial activation in vivo. Glia 2002;40:206–217.

    Article  PubMed  Google Scholar 

  2. Stoll G, Jander S. The role of microglia and macrophages in the pathophysiology of the CNS. Prog Neurobiol 1999;58:233–247.

    Article  PubMed  CAS  Google Scholar 

  3. Banati RB, Egensperger R, Maassen A, Hager G, Kreutzberg GW, Graeber MB. Mitochondria in activated microglia in vitro. J Neurocytol 2004;33:535–541.

    Article  PubMed  Google Scholar 

  4. Ladeby R, Wirenfeldt M, Garcia-Ovejero D, Fenger C, Dissing-Olesen L, Dalmau I, et al. Microglial cell population dynamics in the injured adult central nervous system. Brain Res Brain Res Rev 2005;48:196–206.

    Article  PubMed  CAS  Google Scholar 

  5. Cicchetti F, Brownell AL, Williams K, Chen YI, Livni E, Isacson O. Neuroinflammation of the nigrostriatal pathway during progressive 6-OHDA dopamine degeneration in rats monitored by immunohistochemistry and PET imaging. Eur J Nerurosci 2002;15:991–998.

    Article  CAS  Google Scholar 

  6. Cagnin A, Brooks DJ, Kennedy AM, Gunn RN, Myers R, Turkheimer FE, et al. In-vivo measurement of activated microglia in dementia. Lancet 2001;358:461–467.

    Article  PubMed  CAS  Google Scholar 

  7. Hammoud DA, Endres CJ, Chander AR, Guilarte TR, Wong DF, Sacktor NC, et al. Imaging glial cell activation with [11C]-R-PK 11195 in patients with AIDS. J Neurovirol 2005;11:346–355.

    Article  PubMed  CAS  Google Scholar 

  8. Debruyne JC, Van Laere KJ, Versijpt J, De Vos F, Eng JK, Striickmans K, et al. Semiquantification of the peripheral-type benzodiazepine ligand [11C]PK11195 in normal human brain and application in multiple sclerosis patients. Acta Neurol Belg 2002;102:127–135.

    PubMed  Google Scholar 

  9. Zhang MR, Maeda J, Ogawa M, Noguchi J, Ito T, Yoshida Y, et al. Development of a new radioligand, N-(5-fluoro-2-phenoxyphenyl)-N-(2-[18F]fluoroethyl-5-methoxybenzyl) acetamide, for PET imaging of peripheral benzodiazepine receptor in primate brain. J Med Chem 2004;47:2228–2235.

    Article  PubMed  CAS  Google Scholar 

  10. Groom GN, Junck L, Foster NL, Frey KA, Kuhl DE. PET of peripheral benzodiazepine binding sites in the microgliosis of Alzheimer’s disease. J Nucl Med 1995;36:2207–2210.

    PubMed  CAS  Google Scholar 

  11. Shah F, Hume SP, Pike VW, Ashworth S, McDermott J. Synthesis of the enantiomers of [N-methyl-11C]PK 11195 and comparison of their behaviors as radioligands for PK binding sites in rats. Nucl Med Biol 1994;21:573–581.

    Article  PubMed  CAS  Google Scholar 

  12. Takeuchi A, Isobe KI, Miyaishi O, Sawada M, Fan ZH, Nakashima I, et al. Microglial NO induces delayed neuronal death following acute injury in the striatum. Eur J Neurosci 1998;10:1613–1620.

    Article  PubMed  CAS  Google Scholar 

  13. Paxinos G, Watson C. The rat brain in stereotaxic coordinates. 4th ed. San Diego: Academic; 1998.

    Google Scholar 

  14. Watanabe M, Uchida H, Okada K, Shimizu K, Satoh N, Yoshikawa E, et al. A high resolution PET for animal studies. IEEE Trans Med Imaging 1992;11:577–580.

    Article  PubMed  CAS  Google Scholar 

  15. Suzuki M, Hatano K, Sakiyama Y, Kawasumi Y, Kato T, Ito K. Age-related changes of dopamine D 1-like and D 2-like receptor binding in the F344/N rat striatum revealed by positron emission tomography and in vitro receptor autoradiography. Synapse 2001;41:285–293.

    Article  PubMed  CAS  Google Scholar 

  16. Sakiyama Y, Hatano K, Tajima T, Kato T, Kawasumi Y, Suzuki M, et al. An atlas-based image registration method for dopamine receptor imaging with PET in rats. Ann Nucl Med 2007;21:455–462.

    Article  PubMed  Google Scholar 

  17. Momosaki S, Hatano K, Kawasumi Y, Kato T, Hosoi R, Kobayashi K, et al. Rat-PET study without anesthesia: anesthetics modify the dopamine D 1 receptor binding in rat brain. Synapse 2004;54:207–213.

    Article  PubMed  CAS  Google Scholar 

  18. Lassen NA. Neuroreceptor quantitation in vivo by the steadystate principle using constant infusion or bolus injection of radioactive tracers. J Cereb Blood Flow Metab 1992;12:709–716.

    PubMed  CAS  Google Scholar 

  19. Price GW, Ahier RG, Hume SP, Myers R, Manji L, Cremer JE, et al. In vivo binding to peripheral benzodiazepine binding sites in lesioned rat brain: comparison between [3H]PK11195 and [18F]PK14105 as markers for neuronal damage. J Neurochem 1990;55:175–185.

    Article  PubMed  CAS  Google Scholar 

  20. Gunn RN, Lammertsma AA, Hume SP, Cunningham VJ. Parametric imaging of ligand-receptor interactions using a reference tissue model and cluster analysis. In: Carson R, Daule M, Witherspoon P, Herscovitch P, editors. Quantitative functional brain imaging with positron emission tomography. San Diego: Academic; 1998; p. 401–406.

    Google Scholar 

  21. Kropholler MA, Boellaard R, Schuitemaker A, Folkersma H, van Berckel BNM, Lammertsma A. Evaluation of reference tissue models for the analysis of [11C](R)-PK11195 studies. J Cereb Blood Flow Metab 2006;26:1431–1441.

    Article  PubMed  CAS  Google Scholar 

  22. Schuitemaker A, van Berckel BNM, Kropholler MA, Veltman DJ, Scheltens P, Jonker C, et al. SPM analysis of parametric (R)-[11C]-PK11195 binding images: plasma input versus reference tissue parametric methods. Neuroimage 2007;35:1473–1479.

    Article  PubMed  Google Scholar 

  23. Barger SW, Harmon AD. Microglial activation by Alzheimer amyloid precursor protein and modulation by apolipoprotein E. Nature 1997;388:878–881.

    Article  PubMed  CAS  Google Scholar 

  24. Cavanagh JB. The proliferation of astrocytes around a needle wound in the rat brain. J Anat 1970;106:471–487.

    PubMed  CAS  Google Scholar 

  25. Finklestein S, Campbell A, Stoll AL, Baldessarini RJ, Stinus L, Paskevitch PA, et al. Changes in cortical and subcortical levels of monoamines and their metabolites following unilateral ventrolateral cortical lesions in the rat. Brain Res 1983;271:279–288.

    Article  PubMed  CAS  Google Scholar 

  26. Zhang MR, Kida T, Noguchi J, Furutsuka K, Maeda J, Suhara T, et al. [11C]DAA1106: radiosynthesis and in vivo binding to peripheral benzodiazepine receptors in mouse brain. Nucl Med Biol 2003;30:513–519.

    Article  PubMed  CAS  Google Scholar 

  27. Maeda J, Suhara T, Zhang MR, Okauchi T, Yasuno F, Ikoma Y, et al. Novel peripheral benzodiazepine receptor ligand [11C]DAA1106 for PET: an imaging tool for glial cells in the brain. Synapse 2004;52:283–291.

    Article  PubMed  CAS  Google Scholar 

  28. Imaizumi M, Kim HJ, Zoghbi SS, Briard E, Hong J, Musachio JL, et al. PET imaging with [11C]PBR28 can localize and quantify upregulated peripheral benzodiazepine receptors associated with cerebral ischemia in rat. Neurosci Lett 2007;411:200–205.

    Article  PubMed  CAS  Google Scholar 

  29. Imaizumi M, Briard E, Zoghbi SS, Gourley JP, Hong J, Musachio JL, et al. Kinetic evaluation in nonhuman primates of two new PET ligands for peripheral benzodiazepine receptors in brain. Synapse 2007;61:595–605.

    Article  PubMed  CAS  Google Scholar 

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Correspondence to Hiroshi Toyama.

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Toyama, H., Hatano, K., Suzuki, H. et al. In vivo imaging of microglial activation using a peripheral benzodiazepine receptor ligand: [11C]PK-11195 and animal PET following ethanol injury in rat striatum. Ann Nucl Med 22, 417–424 (2008). https://doi.org/10.1007/s12149-008-0136-1

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  • DOI: https://doi.org/10.1007/s12149-008-0136-1

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