FIGURE 3.

Involvement of PKA in aspirin-induced expression of CNTF in primary mouse astrocytes. Cells were incubated with 10 μ m aspirin (Asp) for different minute intervals followed by monitoring the activation of PKA (A) and PKC (B) as described under “Materials and Methods.” Cells were incubated with aspirin for different hour intervals followed by monitoring the activation of PKA (C). Results are mean ± S.D. of three independent experiments. a, p < 0.05; b, p < 0.001 versus control (Con). Cells pretreated with different concentrations of H-89 for 30 min were stimulated with aspirin followed by monitoring the mRNA expression of Cntf by real time PCR (D) and the protein level of CNTF by Western blot (E). Bands were scanned and values presented as relative expression (F). Results are mean ± S.D. of three different experiments. a, p < 0.001 versus control; b, p < 0.05; c, p < 0.001 versus aspirin. Cells were transfected with PKA-siRNA and control siRNA. After 48 h of transfection, the protein level of PKA was monitored by Western blot (G). Bands were quantified and presented as relative to control (H). Results are mean ± S.D. of three independent experiments. a, p < 0.001 versus control. Under similar treatment conditions, the mRNA expression of CNTF was monitored by real time PCR (I). The protein level of CNTF was monitored by Western blot (J). Bands were quantified and presented as relative to control (K). Results are mean ± S.D. of three different experiments. a, p < 0.001 versus control; b, p < 0.001 versus control siRNA-aspirin.