Regular articleInvolvement of benzodiazepine receptors in neuroinflammatory and neurodegenerative diseases: evidence from activated microglial cells in vitro
Section snippets
Cell culture
For all experiments Wistar rats that were bred and held under constant conditions (12h/12h light/dark cycle) in the animal house of the University of Kiel were used Free-floating microglial cells were collected from the medium of primary cell cultures from neonatal rat cerebral cortex after 10 days, as detailed elsewhere Sievers and Parwaresch, 1994, Wilms and Hartmann, 1997, Wilms and Wollmer, 1999: Briefly, free-floating microglia was collected from the medium of primary cell cultures from
Cell morphology and expression of PBR
Within 3 days the seeded microglial cells developed the characteristic ramified shape of resting microglia in vitro with branched cellular processes and a small cell soma (Fig. 1A). After treatment with LPS the microglial cells adopted an amoeboid phenotype characteristic of activated myelomonocytic cells (Fig. 1B). Both resting and activated cells could be immunostained with a specific antibody directed against the PBR (Fig. 1D and E). However, it should be noted that resting microglia (Fig.
Discussion
Peripheral-type benzodiazepine receptors are widely distributed receptors that recognize a subset of benzodiazepine receptors. Although they are expressed in the undamaged CNS at only a low level, it appears that the relative density of PBR is a reliable marker for neuroinflammation and gliosis with neuronal damage (Banati, 2002): Animal studies indicate that neuronal damage experimentally induced by excitoxicity (Altar and Baudry, 1990), ischemia (Stephenson et al., 1995), experimental facial
Acknowledgements
The authors thank Mrs. Rosemarie Sprang for superior technical assistance. This work was supported by a grant from the Hensel-Foundation, University of Kiel (to R.L.) and a generous donation from the “Herbert und Inge Lampe Stiftung” (to H.W. and R.L.).
References (52)
- et al.
The peripheral-type benzodiazepine receptor. Localization to the mitochondrial outer membrane
J. Biol. Chem.
(1986) - et al.
Purification and characterization of a protein associated with peripheral-type benzodiazepine binding sites
J. Biol. Chem.
(1988) - et al.
Characterization of benzodiazepine receptors in the bovine pineal glandevidence for the presence of an atypical binding site
Brain Res.
(1986) - et al.
Peripheral type benzodiazepine binding sites are a sensitive indirect index of neuronal damage
Brain Res.
(1987) - et al.
Immunocytochemical analysis of tumor necrosis factor and its receptors in Parkinson's disease
Neurosci. Lett.
(1994) - et al.
In-vivo measurement of activated microglia in dementia
Lancet
(2001) - et al.
A new aspect of the antiproliferative action of peripheral-type benzodiazepine receptor ligands
Eur. J. Pharmacol.
(1995) - et al.
Isolation, purification and partial sequence of a neuropeptide (diazepam-binding inhibitor) precursor of an anxiogenic putative ligand for benzodiazepine recognition site
Neurosci. Lett.
(1984) - et al.
Gamma-aminobutyric acidA receptor structure and function
J. Biol. Chem.
(1992) - et al.
Stimulation of cell growth and DNA synthesis by peripheral benzodiazepine
Cancer Lett.
(1990)
Microgliaa sensor for pathological events in the CNS
Trends Neurosci.
Enhanced expression of the peripheral benzodiazepine receptor (PBR) and its endogenous ligand octadecaneuropeptide (ODN) in the regenerating adult rat sciatic nerve
Neurosci. Lett.
Regulation of the expression of peripheral benzodiazepine receptors and their endogenous ligands during rat sciatic nerve degeneration and regenerationa role for PBR in neurosteroidogenesis
Brain Res.
In vivo immunomodulating activity of PK 1195, a structurally unrelated ligand for “peripheral” benzodiazepine binding sites. I. Potentiation in mice of the humoral response to sheep red blood cells
Int. J. Immunopharmacol.
Presence of peripheral-type benzodiazepine binding sites on human erythrocyte membranes
Eur. J. Pharmacol.
The peripheral-type benzodiazepine receptor is functionally linked to Leydig cell steroidogenesis
J. Biol. Chem.
Benzodiazepine receptor binding in young, mature and senescent rat brain and kidney
Neurobiol. Aging
Cytokines and the nervous system IIactions and mechanisms of action
Trends Neurosci.
Benzodiazepines protect hippocampal neurons from degeneration after transient cerebral ischemiaan ultrastructural study
Neuroscience
Human, rat, and mouse kidney cells express functional erythropoietin receptors
Kidney Int.
In vitro-staining specificity of the antibody 5-D-4 for microglia but not for monocytes and macrophages indicates that microglia are a unique subgroup of the myelomonocytic lineage
J. Neuroimmunol.
Diazepam-binding inhibitora neuropeptide located in selected neuronal populations of rat brain
Science
Systemic injection of kainic acidgliosis in olfactory and limbic brain regions quantified with [3H]PK 11195 binding autoradiography
Exp. Neurol.
In vivo regulation of peripheral-type benzodiazepine receptor and glucocorticoid synthesis by Ginkgo biloba extract EGb 761 and isolated ginkgolides
Endocrinology
Visualising microglial activation in vivo
Glia
Cytotoxicity of microglia
Glia
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H.W. and J.C. contributed equally to this study.