Fig. 1.

Inhibition of PLCγ1 with U73122 increased Collagen2 and Aggrecan levels in IL‐1β‐treated rat chondrocytes. Rat chondrocytes were treated with IL‐1β at 10, 20, and 40 ng·mL⁻¹ for 36 h. Protein levels of Collagen2 and Aggrecan were analyzed by Western blotting (A). Chondrocytes pretreated with IL‐1β (20 ng·mL⁻¹ for 36 h) were treated with the PLCγ1 inhibitor U73122 at 1, 2, 4, and 6 μm for 12 h. Total and phosphorylated protein levels of PLCγ1, Collagen2, and Aggrecan were analyzed by Western blotting (B). In addition, chondrocytes pretreated with IL‐1β (20 ng·mL⁻¹ for 36 h) were treated with U73122 (2 μm for 12 h), and mRNA levels of Collagen2 and Aggrecan were analyzed by RT‐PCR (C). β‐Actin was used as the control for Western blotting, and GAPDH was used as the control for RT‐PCR. Values are means and standard deviations, the error bars represent SD. One‐way ANOVA with the Dunnett test was used to calculate P values. These results are representative of at least three independent experiments in each experiment. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.