Changes in number of GER cells and apoptotic cells. (A) Number of cells in the GER as a function of age. We counted cells in the GER of both non-Tg and R75W + mice at P8 (n = 5), P10 (n = 5), and P12 (n = 5). For both non-Tg and R75W + mice, there were significantly fewer cells in the GER at P12 than at P8. At P12, there were significantly fewer cells in the GER of non-Tg mice than in R75W + mice. (B) Number of apoptotic cells in the GER as a function of age. We counted apoptotic cells in the GER of both non-Tg and R75W + mice at P8 (n = 5), P10 (n = 5), and P12 (n = 5). In non-Tg mice, there was significantly less apoptosis at P12 than at P8. In R75W + mice, however, there were no significant differences between P8, P10, and P12. At P12, there was significantly less apoptosis in the GER of non-Tg mice than in R75W + mice. These data are expressed as mean ± SEM. *denotes p ≤ 0.05.