Abstract: Objective In order to compare the alteration of reelin-immunoreactive. Cajal-Retzius cells (CR cells) in molecular layer of dentate gyrus of APPswe transgenic mice with wild type, the histochemical and developmental characteristics of CR cells were studied, therefore, the roles of CR cells in Alzheimer’s disease would be revealed further. Methods The Thioflavine S staining, reelin immunofluorescence with or without reelin/glutamate and reelin/GABA immuno-double staining were carried out in the study. In the meantime, Western blotting was used to study the expression of reelin in hippocampi of the both wild type and transgenic mice. Results Reelin positive CR cells could be double-labeled with either glutamate or GABA immunostaining. Caspase-3 immunofluorescence demonstrated that some CR cells went through apoptosis during their development. Compared with wild type, CR cells in APPswe transgenic mice had significantly decreased in the molecular layer of the dentate gyrus. The result was supported with Western blotting analysis of reelin expression in hippocampus. Conclusion Reelin could be co-expressed with either glutamate or GABA, suggesting CR cells would be glutamatergic exciting neurons and GABAergic interneurons. The loss of CR cells during development probably was caused by the neuroapoptosis. Significant decrease of CR cells in hippocampus of APPswe transgenic mice

Key words: Alzheimer disease, Cajal-Retzius cell, Reelin, Thioflavine S staining, Immunofluorescence, Mouse