Fig. 2.

Effect of phased treatment with corticosterone on survival of newly formed cells. (A) Animals received phased excess corticosterone treatment (oil otherwise) following the regimes depicted. (B) Mean ± SE of BrdU cells at time of death; group 1 + 2 + 3 confirms long-term treatment with high corticosterone post-BrdU reduces survival (§P < 0.0001). Phased 9-day treatment during period 1 and 2, but not 3, significantly reduced survival of the newly formed cells (†P < 0.029, ‡P < 0.001), suggesting progenitors are only sensitive to high corticosterone during the first 18 days after mitosis. Further phased high corticosterone treatment to the first 9 days (group 1 vs. 1 + 2) resulted in additional reduction (ΨP < 0.003). However, no significant difference was observed comparing groups 2 and groups 2 + 3.