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Reducing excessive GABA-mediated tonic inhibition promotes functional recovery after stroke


Stroke is a leading cause of disability, but no pharmacological therapy is currently available for promoting recovery. The brain region adjacent to stroke damage—the peri-infarct zone—is critical for rehabilitation, as it shows heightened neuroplasticity, allowing sensorimotor functions to re-map from damaged areas1,2,3. Thus, understanding the neuronal properties constraining this plasticity is important for the development of new treatments. Here we show that after a stroke in mice, tonic neuronal inhibition is increased in the peri-infarct zone. This increased tonic inhibition is mediated by extrasynaptic GABAA receptors and is caused by an impairment in GABA (γ-aminobutyric acid) transporter (GAT-3/GAT-4) function. To counteract the heightened inhibition, we administered in vivo a benzodiazepine inverse agonist specific for α5-subunit-containing extrasynaptic GABAA receptors at a delay after stroke. This treatment produced an early and sustained recovery of motor function. Genetically lowering the number of α5- or δ-subunit-containing GABAA receptors responsible for tonic inhibition also proved beneficial for recovery after stroke, consistent with the therapeutic potential of diminishing extrasynaptic GABAA receptor function. Together, our results identify new pharmacological targets and provide the rationale for a novel strategy to promote recovery after stroke and possibly other brain injuries.

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Figure 1: Increased tonic inhibition in peri-infarct cortex.
Figure 2: Impairment in GABA transport and effect of blocking α5-GABA A receptors after stroke.
Figure 3: Behavioural recovery after stroke with L655,708 treatment and in Gabra5 −/− and Gabrd −/− animals
Figure 4: Inflection point in L655,708 treatment effect on infarct size.


  1. Cramer, S. C. Repairing the human brain after stroke: I. Mechanisms of spontaneous recovery. Ann. Neurol. 63, 272–287 (2008)

    Article  Google Scholar 

  2. Brown, C. E., Aminoltejari, K., Erb, H., Winship, I. R. & Murphy, T. H. In vivo voltage-sensitive dye imaging in adult mice reveals that somatosensory maps lost to stroke are replaced over weeks by new structural and functional circuits with prolonged modes of activation within both the peri-infarct zone and distant sites. J. Neurosci. 29, 1719–1734 (2009)

    CAS  Article  Google Scholar 

  3. Dijkhuizen, R. M. et al. Correlation between brain reorganization, ischemic damage, and neurologic status after transient focal cerebral ischemia in rats: a functional magnetic resonance imaging study. J. Neurosci. 23, 510–517 (2003)

    CAS  Article  Google Scholar 

  4. Dobkin, B. H. Training and exercise to drive poststroke recovery. Nature Clin. Pract. Neurol. 4, 76–85 (2008)

    Article  Google Scholar 

  5. Carmichael, S. T. Cellular and molecular mechanisms of neural repair after stroke: making waves. Ann. Neurol. 59, 735–742 (2006)

    CAS  Article  Google Scholar 

  6. Nudo, R. J. Mechanisms for recovery of motor function following cortical damage. Curr. Opin. Neurobiol. 16, 638–644 (2006)

    CAS  Article  Google Scholar 

  7. Alonso-Alonso, M., Fregni, F. & Pascual-Leone, A. Brain stimulation in poststroke rehabilitation. Cerebrovasc. Dis. 24 (suppl. 1). 157–166 (2007)

    Article  Google Scholar 

  8. Di Lazzaro, V. et al. Motor cortex plasticity predicts recovery in acute stroke. Cereb. Cortex 20, 1523–1528 (2010)

    Article  Google Scholar 

  9. Hensch, T. K. Critical period plasticity in local cortical circuits. Nature Rev. Neurosci. 6, 877–888 (2005)

    CAS  Article  Google Scholar 

  10. Donoghue, J. P., Suner, S. & Sanes, J. N. Dynamic organization of primary motor cortex output to target muscles in adult rats. II. Rapid reorganization following motor nerve lesions. Exp. Brain Res. 79, 492–503 (1990)

    CAS  Article  Google Scholar 

  11. Foeller, E., Celikel, T. & Feldman, D. E. Inhibitory sharpening of receptive fields contributes to whisker map plasticity in rat somatosensory cortex. J. Neurophysiol. 94, 4387–4400 (2005)

    Article  Google Scholar 

  12. Hess, G., Aizenman, C. D. & Donoghue, J. P. Conditions for the induction of long-term potentiation in layer II/III horizontal connections of the rat motor cortex. J. Neurophysiol. 75, 1765–1778 (1996)

    CAS  Article  Google Scholar 

  13. Glykys, J. & Mody, I. Hippocampal network hyperactivity after selective reduction of tonic inhibition in GABAA receptor α5 subunit-deficient mice. J. Neurophysiol. 95, 2796–2807 (2006)

    CAS  Article  Google Scholar 

  14. Walker, M. C. & Semyanov, A. Regulation of excitability by extrasynaptic GABA(A) receptors. Results Probl. Cell Differ. 44, 29–48 (2008)

    CAS  Article  Google Scholar 

  15. Collinson, N. et al. Enhanced learning and memory and altered GABAergic synaptic transmission in mice lacking the α5 subunit of the GABAA receptor. J. Neurosci. 22, 5572–5580 (2002)

    CAS  Article  Google Scholar 

  16. Atack, J. R. et al. L-655,708 enhances cognition in rats but is not proconvulsant at a dose selective for α5-containing GABAA receptors. Neuropharmacology 51, 1023–1029 (2006)

    CAS  Article  Google Scholar 

  17. Keros, S. & Hablitz, J. J. Subtype-specific GABA transporter antagonists synergistically modulate phasic and tonic GABAA conductances in rat neocortex. J. Neurophysiol. 94, 2073–2085 (2005)

    CAS  Article  Google Scholar 

  18. Glykys, J. & Mody, I. Activation of GABAA receptors: views from outside the synaptic cleft. Neuron 56, 763–770 (2007)

    CAS  Article  Google Scholar 

  19. Yoshiike, Y. et al. GABAA receptor-mediated acceleration of aging-associated memory decline in APP/PS1 mice and its pharmacological treatment by picrotoxin. PLoS ONE 3, e3029 (2008)

    ADS  Article  Google Scholar 

  20. Cui, Y. et al. Neurofibromin regulation of ERK signaling modulates GABA release and learning. Cell 135, 549–560 (2008)

    CAS  Article  Google Scholar 

  21. Ginsberg, M. D. Neuroprotection for ischemic stroke: past, present and future. Neuropharmacology 55, 363–389 (2008)

    CAS  Article  Google Scholar 

  22. Que, M. et al. Changes in GABA(A) and GABA(B) receptor binding following cortical photothrombosis: a quantitative receptor autoradiographic study. Neurosci. Lett. 93, 1233–1240 (1999)

    CAS  Article  Google Scholar 

  23. Redecker, C., Luhmann, H. J., Hagemann, G., Fritschy, J. M. & Witte, O. W. Differential downregulation of GABAA receptor subunits in widespread brain regions in the freeze-lesion model of focal cortical malformations. J. Neurosci. 20, 5045–5053 (2000)

    CAS  Article  Google Scholar 

  24. Frahm, C. et al. Regulation of GABA transporter mRNA and protein after photothrombotic infarct in rat brain. J. Comp. Neurol. 478, 176–188 (2004)

    CAS  Article  Google Scholar 

  25. Neumann-Haefelin, T. et al. Immunohistochemical evidence for dysregulation of the GABAergic system ipsilateral to photochemically induced cortical infarcts in rats. Neuroscience 87, 871–879 (1998)

    CAS  Article  Google Scholar 

  26. Kharlamov, E. A., Downey, K. L., Jukkola, P. I., Grayson, D. R. & Kelly, K. M. Expression of GABAA receptor α1 subunit mRNA and protein in rat neocortex following photothrombotic infarction. Brain Res. 1210, 29–38 (2008)

    CAS  Article  Google Scholar 

  27. Lee, J. K., Kim, J. E., Sivula, M. & Strittmatter, S. M. Nogo receptor antagonism promotes stroke recovery by enhancing axonal plasticity. J. Neurosci. 24, 6209–6217 (2004)

    CAS  Article  Google Scholar 

  28. Tanaka, Y., Furuta, T., Yanagawa, Y. & Kaneko, T. The effects of cutting solutions on the viability of GABAergic interneurons in cerebral cortical slices of adult mice. J. Neurosci. Methods 171, 118–125 (2008)

    CAS  Article  Google Scholar 

  29. Baskin, Y. K., Dietrich, W. D. & Green, E. J. Two effective behavioral tasks for evaluating sensorimotor dysfunction following traumatic brain injury in mice. J. Neurosci. Methods 129, 87–93 (2003)

    Article  Google Scholar 

  30. Ohab, J. J., Fleming, S., Blesch, A. & Carmichael, S. T. A neurovascular niche for neurogenesis after stroke. J. Neurosci. 26, 13007–13016 (2006)

    CAS  Article  Google Scholar 

  31. Lee, K., Kim, J. E., Sivula, M. & Strittmater, S. M. Nogo receptor antagonism promotes stroke recovery by enhamcing axonal plasticity. J. Neurosci. 24, 6209–6217 (2004)

    CAS  Article  Google Scholar 

  32. Glykys, J., Mann, E. O. & Mody, I. Which GABAA receptor subunits are necessary for tonic inhibition in the hippocampus? J. Neurosci. 28, 1421–1426 (2008)

    CAS  Article  Google Scholar 

  33. STAIR Recommendations for standards regarding preclinical neuroprotective and restorative drug development. Stroke. 30, 2752–2758 (1999)

    Article  Google Scholar 

  34. Fisher, M., Feuerstein, G., Howells, D. W., Hurn, P. D., Kent, T. A., Savitz, S. I. & Lo, E. H. Update of the stroke therapy academic industry roundtable preclinical recommendations. Stroke. 40, 2244–2250 (2009)

    Article  Google Scholar 

  35. Stell, B. & Mody, I. Receptors with different affinities mediate phasic and tonic GABAA conductances in hippocampal neurons. J. Neurosci. 22, RC223 (2002)

    Article  Google Scholar 

  36. Verheugen, J. A., Fricker, D. & Miles, R. Noninvasive measurements of the membrane potential and GABAergic action in hippocampal interneurons. J. Neurosci. 19, 2546–2555 (1999)

    CAS  Article  Google Scholar 

  37. Barlow, R. Cumulative frequency curves in population analysis. Trends Pharmacol. Sci. 11, 404–406 (1990)

    CAS  Article  Google Scholar 

  38. Baskin, Y. K., Dietrich, W. D. & Green, E. J. Two effective behavioral tasks for evaluating sensorimotor dysfunction following traumatic brain injury in mice. J. Neurosci. Methods 129, 87–93 (2003)

    Article  Google Scholar 

  39. Schallert, T., Fleming, S. M., Leasure, J. L., Tillerson, J. L. & Bland, S. T. CNS plasticity and assessment of forelimb sensorimotor outcome in unilateral rat models of stroke, cortical ablation, parkinsonism and spinal cord injury. Neuropharmacology 39, 777–787 (2000)

    CAS  Article  Google Scholar 

  40. Moore, C. S. et al. Increased X-linked inhibitor of apoptosis protein (XIAP) expression exacerbates experimental autoimmune encephalomyelitis (EAE). J. Neuroimmunol. 203, 79–93 (2008)

    CAS  Article  Google Scholar 

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I.M., A.N.C. and S.T.C. were supported by The Dr. Miriam and Sheldon G. Adelson Medical Research Foundation. S.T.C. was supported by the Larry L. Hillblom Foundation, I.M. was supported by the Coelho Endowment and National Institutes of Health/National Institute of Neurological Disorders and Stroke grant NS30549. This manuscript was completed partially during tenure of an American Heart Association Postdoctoral Fellowship, a Repatriation Fellowship from the New Zealand Neurological Foundation and the Sir Charles Hercus Fellowship from the Health Research Council of New Zealand (A.N.C.). We thank E. O. Mann, J. Chu, J. J. Overman, J. Zhong and R. M. Lazaro for discussion and assistance.

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A.N.C. performed the behavioural, histological and immunohistochemical studies; B.S.H. carried out the electrophysiological experiments; and S.E.M. performed the immunohistochemical and western blot work. A.N.C., B.S.H., I.M. and S.T.C. designed the experiments, analysed data, prepared figures and wrote the manuscript.

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Correspondence to S. Thomas Carmichael.

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Clarkson, A., Huang, B., MacIsaac, S. et al. Reducing excessive GABA-mediated tonic inhibition promotes functional recovery after stroke. Nature 468, 305–309 (2010).

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