CD150 is heterogeneous with respect to dye efflux and changes with age within the SP. (A) The analysis scheme divides the SP into upper and lower portions, both of which are heterogeneous with respect to CD150. These relations are quantified in subsequent panels. Percentages shown correspond to the gated proportion of the plot. (B) The proportion of CD150⁺ cells increases with age within the SP. (C) When the shift in CD150⁺ SP cells is quantified, there is a significant change with age, which varies between upper and lower SP. Error bars represent SEM.