Identification of α7 nicotinic acetylcholine receptor on hippocampal astrocytes cultured in vitro and its role on inflammatory mediator secretion★

The present study found expressions of α7 nicotinic acetylcholine receptor on hippocampal slices and hippocampal astrocytes using double immunofluorescence stainings. Expression of glial fibrillary acidic protein in the cultured hippocampal slices and hippocampal astrocytes significantly increased, and levels of macrophage inflammatory protein 1α, RANTES, interleukin-1β, interleukin-6, and tumor necrosis factor-α increased in the supernatant of cultured astrocytes following exposure to 200 nM amyloid β protein 1–42. Preconditioning of 10 μM nicotine, a nicotinic acetylcholine receptor agonist, could attenuate the influence of amyloid β protein 1–42 in inflammatory mediator secretion of cultured astrocytes. Experimental findings indicated that α7 nicotinic acetylcholine receptor was expressed on the surface of hippocampal astrocytes, and activated α7 nicotinic acetylcholine receptor was shown to inhibit inflammation induced by amyloid β protein 1–42.