Figure 6. Pro-inflammatory cytokines inhibit abcb1 mRNA expression.

Abcb1 mRNA expression in brain endothelial cell (BEC) cultures derived from postnatal day (PND) 14 male guinea pigs following treatment with 10³ and 3.3×10³ pg/mL A–B) interleukin-1β (IL-1β), C–D) interleukin-6 (IL-6) or E–F) tumor necrosis factor-α (TNF-α) for 4 (A,C,E) or 24 hours (B,D,F) (N = 7–8). Expression is displayed as percent of untreated control cell expression (i.e. 100% line) and taken over the reference gene, beta-actin. Values displayed as mean ± S.E.M. A significant difference from control indicated by (**) P<0.01; (***) P<0.001.