TLR4 inhibition increases endothelial modulation of vasoconstrictor responses.

<p>Concentration-response curves to phenylephrine in intact (E+) and endothelium denuded (E−) aortic segments from (A) Wistar and (B) SHRs treated with a non-specific IgG (1 µg/day, 15 days) and (C) SHRs treated with anti-TLR4 antibody (1 µg/day, 15 days). (D) Differences in the area under the concentration-response curve (dAUC) in the E– and E+ segments; AUC was calculated from the individual curve plots; the differences are expressed as a percentage of the AUC for the corresponding control situation. (E) Contractile response to L-NAME (100 µM) after phenylephrine (1 µM) contraction in segments from Wistar and SHRs treated with a non-specific IgG and SHRs treated with anti-TLR4 antibody; the results are expressed as the percentage of the previous contraction induced by phenylephrine. The results are the mean±SEM. *P<0.05 <i>vs.</i> E+ or <i>vs</i>. Wistar, #P<0.05 <i>vs.</i> SHR using two-way ANOVA and Bonferroni post-test. The number of animals used is shown in parentheses.