Effect of penehyclidine on Toll-like receptor 4 mRNA and Toll-like receptor 2 mRNA expression in rats with acute lung injury induced by lipopolysaccharide

Abstract

Objective To investigate the effect of penehyclidine (PHCD) on Toll-like receptor 4 (TLR4)mRNA and Toll-like receptor 2 (TLR2) mRNA expression in the lung tissue in rats with acute lung injury induced by lipopolysaccharide (LPS) .Methods Sixty healthy SD rats of both sexes weighing 200-220 g were randomly divided into 5 groups ( n = 12 each) :control group (group C) , LPS group and P1-3 groups. Acute lung injury was induced by intraperitoneal (IP) LPS 8 mg/kg in LPS and P1-3 groups. PHCD 0.3, 1.0 and 3.0 mg/kg were given IP after LPS administration in P1-3 groups. The animals were anesthetized at 6 h after IP LPS. Blood samples were collected for determination of serum TNF-α and IL-6 concentrations ( by ELISA) and then sacrificed, the lungs were immediately removed for determination of TLR4 mRNA and TLR2 mRNA expression (by RT-PCR), and microscopic examination. Results LPS significantly increased TLR4 mRNA and TLR2 mRNA expression in the lung tissue and serum TNF-α and IL-6 concentrations. PHCD 1.0 or 3.0 mg/kg significantly inhibited LPS-induced increase in TLR4 mRNA and TLR2 mRNA expression in the lung tissue and serum TNF-α and ILr6 concentrations.The lung histopathologic damage was significantly ameliorated in P2 and P3 groups as compared with group LPS.Conclusion PHCD can protect the lungs against LPS-induced acute lung injury through inhibiting TLR4 mRNA and TLR2 mRNA expression in the lung tissue and reducing the inflammatory response. Key words: Cholinergic antagonists; Toll-like receptor 2; Toll-like receptor 4; Endotoxemia; Respiratory distress syndrome, adult