Fig. 6.
G-CSF enhances cocaine-induced locomotor sensitization and CPP. (a—top) Experimental timeline of locomotor sensitization to cocaine. Mice (n = 4 PBS, 5 G-CSF) were i.p. injected with G-CSF (50 µg kg−1) or PBS 1 h before monitoring locomotor activity following an injection of saline or cocaine (7.5 mg kg−1). (a—bottom) Locomotor sensitization to cocaine was increased in mice pre-treated with G-CSF (repeated-measures two-way ANOVA; time: F (6,42) = 33.16, p < 0.0001; G-CSF: F(1,7) = 8.808, p = 0.021; interaction: F(6,42) = 3.942; p = 0.0032). b For cocaine conditioned place preference, mice were injected with G-CSF (50 µg kg−1) or PBS 1 h every day before testing. Two-way ANOVA testing demonstrated a main effect of G-CSF (F(1,36) = 11.76, p = 0.0015), and Holm-Sidak post-hoc testing demonstrated increased CPP in G-CSF-treated mice conditioned with 3.75 mg kg−1 of cocaine (PBS n = 6; G-CSF: n = 9; p < 0.05 vs PBS), 7.5 mg kg−1 (PBS: n = 6; G-CSF: n = 10; p < 0.05 vs PBS) of cocaine but not with 15 mg kg−1 (PBS: n = 5; G-CSF: n = 6). (*p < 0.05, **p < 0.01 for Holm-Sidak post-hoc tests; # p < 0.05, ## p < 0.01 for two-way ANOVA main effects)