Fig 2.

Permeability of RLEC monolayers to FITC-labled bovine serum albumin in response to inflammatory cytokines TNF-α (10ng/mL), Il-6 (100ng/mL), Il-1β (50ng/mL), LPS (50ng/mL) IFN-γ (10ng/mL). These treatments were carried out alone and in the presence of 1μM LNAME to test NO dependency of permeability (a). Western blot of TNF-α, IL-6 and IL-1β treated cells at 24 hrs showing that IL-1β alone out of all tested cytokines induces an up regulation of iNOS (b). Specific cytokines (IFN-γ, IL-1β and TNF-α) were selected for further testing of NO production by Griess assay. TNF-α was used to test the efficacy of LNAME on NO production (after 24 hr to allow accumulation of nitrite), while IFN-γ and IL-1β represented the cytokines that had the greatest NO-dependent and NO-independent permeability effects respectively (c). Permeability data is representative from 6 experiments, n=3–6. Greiss assay data is representative of 3 experiments with n=3. * denotes significant departure from control (p≤0.05) as determined by ANOVA with Dunnett's post test.