Fig. 8. Small interfering RNA (siRNA) knockdown of cyclin D1 attenuates ketamine-induced increases in Bcl2-interacting mediator of cell death (Bim) and cleaved caspase-3. (A ) Primary neurons were transfected with cyclin D1-siRNA (siRNA) or scrambled control-siRNA (control) for 6 h and exposed to 10 μm ketamine or control medium for 24 h. Knockdown of cyclin D1 by siRNA resulted in decreased expression of Bim and cleaved caspase-3. (B ) Quantitation of immunoreactive band densities normalized to β-actin confirm the attenuation of Bim and cleaved caspase-3 in ketamine-treated primary neurons transfected with cyclin D1-siRNA (n = 3, **P < 0.05, compared with the control group). Dataare presented as mean ± standard error. K = ketamine.