FIGURE 3.
Effect of IL-1β on Caco-2 MLCK activity. A, Time course effect of IL-1β on MLCK activity of filter-grown Caco-2 monolayers was determined by ELISA-based in vitro kinase activity measurements as described in Materials and Methods. After appropriate time period, MLCK activity was assessed by measuring the in vitro phosphorylation of MLC (S-19). IL-1β treatment resulted in a time-dependent increase in Caco-2 MLCK activity. *, p < 0.05 vs control. B, Time course effect of IL-1β on phosphorylation of MLC (P-MLC) in filter-grown Caco-2 monolayers over the 48-h experimental period as determined by Western blot analysis. C, Pretreatment with cycloheximide (5 μM) inhibited the IL-1β-induced increase in MLCK kinase activity, cycloheximide alone did not affect MLCK enzyme activity. *, p < 0.001 vs control; **, p < 0.001 vs IL-1β treatment.