GFAP and Cerebral ischemia: To identify cell types expressing PACAP38 after cerebral ischemia, double immunofluorescence staining under laser scanning confocal microscopy was used to observe the expression patterns of PACAP38 in colocalization with neuronal marker of Neu-N, glial marker of GFAP, and endothelial marker of vWF in the ischemic brains.