Figure 5. Rapamycin worked as autophagy agonist and the anti-apoptosis effect of rapamycin was analyzed in vitro. Chondrocytes of the IL-18 + rapamycin treatment group were pre-treated with rapamycin (100 nM) for 1 h, followed with 24 h IL-18 stimulation (100 ng/ml). Chondrocytes of the IL-18 treatment group were treated with 100 ng/ml IL-18 for 24 h. Chondrocytes of the rapamycin treatment group were treated with 100 nM rapamycin for 24 h. Protein levels of Bax (B) Bcl2 (C) Cleaved-Caspase3 (D) Caspase3 (E) Cleaved Caspase9 (F) Caspase9 (G) and GAPDH as an internal control, evaluated by Western blot (A). The values are expressed as mean ± standard deviation (SD). Significance was calculated by a one-way ANOVA with a post hoc Tukey's multiple comparisons test. *p<0.05 versus the IL-18 treatment group.