Figure 6.

LTB₄ induced Nox4 expression, hydrogen peroxide (H₂O₂) production and HPAAF activation. A, HPAAFs were treated with LTB₄ at concentrations of 200 and 400nM; H₂O₂ production was measured by Amplex assay and B, Nox4 expression was determined by western blot. C, After pretreatment with U75302 (1μM), SB203580 (10μM) or the Nox4 inhibitor apocynin (300μM), the effects of exogenous LTB₄ on HPAAFs were assayed. H₂O₂ production was measured by the Amplex assay. D, Western blots were used to determine the expression of Nox4, p-p38 MAPK and total p38 MAPK; β-actin was used as a loading control. E, MTT assay, F, cell counting, G, BrdU assay, H, PCNA expression, I, J, migration and K, differentiation were determined with Nox inhibition (apocynin) in the presence of LTB₄. (^#: Note again in Figure 6D, increased p38 phosphorylation in the SB203580-treated group likely due to this agent inhibiting p38 catalytic activity without affecting phosphorylation of p38 as described in Figure 3D).⁴⁵ (*: p<0.05) The experiments were repeated three times.