CREB protein levels in hippocampal neurons of mouse brain. (A) Western blot analyses of CREB and synaptophysin were carried out with mouse hippocampal samples from 15-19 month old nontransgenic (Ntg) and Tg2576 mice. The blots were reprobed for β Actin. (B) The band intensities were quantitated by scanning. * p < 0.01 vs nontransgenic. (C) Hippocampal sections from Tg2576 mice of different ages were immunostained for CREB. Representative images from dentate gyrus regions are presented. (D) The intensities of CREB stain in hippocampal neurons of different regions were quantitated by ImagepPro analysis. * p < 0.05 vs nontransgenic control of 9 month old mice. ** p < 0.01 compared to nontransgenic control at respective age.