Figure 3.

0.7% ISO reduces ZY-induced p38 MAPK activation; p38 MAPK signaling is essential to ZY-induced NF-κB activation and COX2/PGE₂ generation in vitro. (a) At 0.5 h after ZY or CM (Ctrl) treatment, KCs (1 × 10⁶ cells/well in six-well culture plates) were exposed to RA with or without 0.7% ISO for 0.5 h. The cells were continuously stimulated with Ctrl for 0 h and 6 h or ZY (0.5 mg/mL) for 0.5, 1, 2, 3, and 6 h. Western blot analysis was used to assess the phosphorylation of p38 MAPK (Thr180/Tyr182), JNK (Thr183/Tyr185), and ERK1/2 (Thr185/Tyr187). β-Actin was used as the internal control. The ratio from p-p38 MAPK to p38 MAPK is indicated above the bands. (b) The KCs with or without SB202190 (10 μM) pretreatment for 0.5 h were treated with ZY (0.5 mg/mL) or Ctrl for 1 h. Western blot was performed to determine the phosphorylation of IKKβ (Ser180). β-Actin was used as the internal control. The ratio from pIKKβ to IKKβ is indicated above the bands. (c) The KCs with or without SB202190 (10 μM) pretreatment for 0.5 h were treated with ZY (0.5 mg/mL) or Ctrl for 24 h. RIA was performed to detect PGE₂ release. Representative data are from three independent experiments and expressed as mean ± SD. *P < 0.05 versus Ctrl + RA or Ctrl + ISO; ^# P < 0.05 versus ZY + RA. “Time” in the figure represents the time periods of Ctrl or ZY treatment. ZY: zymosan; ISO: isoflurane; Ctrl: control; RA: room air.