Activation of the α7 nicotinic acetylcholine receptor upregulates blood-brain barrier function through increased claudin-5 and occludin expression in rat brain endothelial cells.

•α7 nAChR agonist tightens the brain endothelial tight junction barrier.•α7 nAChR agonist increases claudin-5 and occludin in brain endothelial cells.•Varenicline and nicotine (non-selective nAChR agonist) do not exhibit these effects.•Brain endothelial α7 nAChR is a positive regulator of blood-brain barrier function.