Figure 8.

C5aR1 signaling cause ALI development in severe experimental envenomation by N. annulifera. Mice (n=6/group) were pretreated with PMX205 (2 mg/ kg), a C5aR1 inhibitor, or vehicle 24 and 1 hour before of N. annulifera venom (NaV) injection. Following inhibitor or vehicle administration, severe systemic reactions were induced by the injection of NaV lethal dose, via intraperitoneal route. Five hours after envenomation, the lungs were obtained, fixed, and submitted to histologic procedures (A) Results were expressed as area of alveolar collapse (%) (B) and histopathological scores (C, D), i.e., 1- mild changes; 2- moderate changes; 3- severe/intense changes. Data are means ± SEM of six independent experiments. ***p ≤ 0.001 (two-tailed t-test or two-way ANOVA, followed by Bonferroni posttest). ^### indicates a significant difference between animals treated with NaV + Vehicle and NaV + PMX205.