Early propranolol treatment amelioratesendothelial dysfunction in experimental septic lung

BACKGROUND: Recent reports have indicated an improved prognosis in sepsis with β-blocker agents; however, the underlying action mechanism is still under debate. OBJECTIVES: The aim of this study was to investigate the potential effect of propranolol on endothelial dysfunction in septic rats. MATERIAL AND METHODS: The cecal ligation and puncture model (CLP) was used to generate sepsis. Adult male Wistar-Albino rats were divided into 4 groups: group 1 was a sham group, group 2 received sterile saline, group 3 received 10 mg/kg of propranolol 3 days before the intervention, and group 4 received 10 mg/kg of propranolol 30 min after CLP. Six rats from each group were sacrificed 24 h postoperatively. The remaining rats were followed for survival. We have also evaluated the effects on systemic inflammation, coagulation and the lung tissue with immunohistochemical and electron microscopic evaluation. RESULTS: Serum tumor necrosis factor alpha (TNF-α) and plasminogen activator inhibitor-1 (PAI-1) levels, as well as tissue TNF-α scores were elevated in septic rats. Electron microscopic examination of the lung tissue showed endothelial dysfunction in the sepsis group. Pretreatment significantly improved survival. Moreover, pre-treatment altered serum vascular endothelial growth factor receptor-1 (VEGFR-1) levels and post-treatment reduced serum PAI-1 and VEGFR-1 levels. In both the preand post-treatment groups, electron microscopic examination revealed improvement of the destroyed lung endothelium and showed only mild alterations in the cytoplasmic organelles, especially in the mitochondria of the endothelial cells. CONCLUSIONS: These results suggest that the improved outcome with β-blockers in sepsis may be due to the ameliorated endothelial dysfunction. Further studies focusing on the potential effect of β-blockers on the endothelium may lead to a better understanding of sepsis.