Role of nitric oxide in Toll-like receptor 2 and 4 mRNA expression in liver of acute hemorrhagic necrotizing pancreatitis rats

Abstract

Aim: To investigate the role of nitric oxide (NO) in Toll-like receptor 2 (TLR2)/4mRNA expression in livers of acute hemorrhagic necrotizing pancreatitis (AHNP) rats. Methods: One hundred and ten SD male rats were randomly divided into sham-operated group (n = 10), AHNP group (n = 30), chloroquine (CQ)-treated group (n = 30) and L-Arg-treated group (n = 40). TLR2/4mRNA expression in the liver of AHNP rats was measured by RT-PCR. Results: Expression of TLR2/4mRNA could be detected in the liver of AHNP rats in sham-operated group (0.155E-5 ± 0.230E-6 and 0.115E-2 ± 0.545E-4), but was markedly increased at 3 h in AHNP group (0.197E-2 ± 0.114E-3 and 0.175 ± 0.349E-2) peaking at 12 h (0.294E-2 ± 0.998E-4 and 2.673 ± 2.795E-2, P < 0.01). Hepatic injuries were aggravated, TNF-α concentration in the liver was increased and NO concentration was decreased (P < 0.05 or P < 0.01). When TLR2/4mRNA expression was inhibited by CQ (3 h: 1.037E-4 ± 3.299E-6 and 0.026 ± 3.462E-3; 6 h: 1.884E-4 ± 4.679E-6 and 0.108 ± 6.115E-3; 12 h: 2.443E-4 ± 7.714E-6 and 0.348 ± 6.807E-3; P < 0.01), hepatic injuries were relieved, NO concentration in the liver was increased and TNF-α concentration was decreased (P < 0.05 or P < 0.01). When rats with AHNP were treated with L-Arg, TLR2/4mRNA expression in the liver could be effectively inhibited (50 mg-T: 0.232E-2 ± 0.532E-4 and 0.230 ± 6.883E-3; 100 mg-T: 0.210E-2 ± 1.691E-4 and 0.187 ± 0.849E-2; 200 mg-T: 0.163E-2 ± 0.404E-4 and 0.107 ± 0.195E-2; 400 mg-T: 0.100E-2 ± 0.317E-4 and 0.084 ± 0.552E-2; P < 0.01) and hepatic injuries were relieved. At the same time, NO concentration in the liver was markedly increased and TNF-α concentration was decreased (P < 0.05 or P < 0.01). Conclusion: The expression of TLR2/4mRNA is increased and hepatic injuries are aggravated in the liver of AHNP rats. TLR2/4mRNA gene expression in the liver of AHNP rats can be markedly inhibited by NO, leading to the relief of hepatic injuries. © 2006 The WJG Press. All rights reserved.