Fig. 1.

Experimental paradigms of BrdUrd labeling. (A) Mice were injected with 1 mg/kg 13-cis-RA or vehicle daily for 1-6 weeks. After this period, the mice were injected with BrdUrd at 50 mg/kg every 2 h over a 6-h period. The brains were then perfused, sectioned, and immunostained, and the number of BrdUrd-labeled cells was counted in every 12th section in the hippocampal formation and SVZ. (B) The mice were injected with BrdUrd at 50 mg/kg every 2 h over a 6-h period, and the mice were allowed to survive for another 3 weeks with continued daily RA injections. The animals were then killed and processed as described above and stained for BrdUrd or double labeled for BrdUrd and the neuronal marker Neu-N.