GH treatment promotes the proliferation of SGZ neurospheres. A) Neurospheres growing in defined media were treated for 24 h with GH (500 ng/mL), pegvisomant (Peg, 20 μg/mL), or GH + pegvisomant. Control cells were treated with saline. Four hours before the end of the treatment period cells were given a BrdU pulse (10 μM). Neurospheres were then dissociated, cells were collected by centrifugation onto coated cover slips, and BrdU was detected by immunocytochemistry. Each bar represents the mean + SEM of 3 experiments in triplicate. * = p < 0.05 vs Control; ° = p <0.05 vs Control and GH. B) Representative images of results presented in A. Scale bar = 10 μm. C) Neurospheres growing in defined media without EGF and FGF2 were treated for 24 h with GH or saline, and BrdU incorporation was detected as indicated. Each bar represents the mean + SEM of 3 experiments in triplicate.