Increased expression of α7 receptors was observed in microglia and astrocytes after cerebral ischaemia. The role of α7 receptors in the neuroinflammatory response to cerebral ischemia was supported by the decrease of [18F]DPA-714 binding in ischemic rats treated with PHA 568487. In addition, treatment with PHA 568487 significantly reduced cerebral infarct volumes and improved neurological outcomes compared with control. Activation of α7 nAChRs had no influence on blood brain barrier permeability8.
Taken together, these results suggest that the nicotinic α7 nAChRs play a key role in the inflammatory reaction and the leukocyte recruitment following cerebral ischemia in rats
It is hoped that the new information obtained in this study supporting the involvement of α7 nAChRs in the development of neuroinflammation after cerebral ischemia may facilitate the development of novel strategies to reduce disability after ischemic stroke and treatments to reduce the burden of other neurological diseases.
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