Table 1.

Survival of BrdU⁺ cells and neurogenesis

	Control	Runner
BrdU+ cells	1,286 (144)	2,956 (274)*
BrdU+/mm3	3,303 (357)	7,153 (555)*
% neurons	81 (2.5)	85 (2.1)
Total neurons	1,062 (143)	2,483 (219)*
Neurons/mm3	2,731 (362)	6,009 (432)*
Volume, mm3	0.45 (0.0082)	0.47 (0.0087)

Adult C57BL/6 mice (n = 20) were assigned to either the control (n = 9) or runner (n = 11) group after completion of shaping and before the onset of task training in the touch-screen system. Mice received five daily BrdU (50 mg/kg) injections. Survival, density of BrdU-labeled cells, and volume of the dentate gyrus were determined 10 weeks after the last BrdU injection. Phenotype of the surviving cells was determined by immunofluorescent double-labeling for BrdU and NeuN (neurons). The density and percentage of BrdU-positive cells double-labeled for NeuN are presented. All data are presented as means (SE).

*Significantly different from controls (P < 0.0001).