Effect of nitric oxide on toll-like receptor 2 and 4 gene expression in rats with acute lung injury complicated by acute hemorrhage necrotizing pancreatitis

BACKGROUND: Toll-like receptor (TLR) 2/4 might play important roles in mediating proinflammatory cytokine synthesis and release. And nitric oxide (NO) has been used to treat acute respiratory distress syndrome (ARDS). This study aimed to investigate the changes in TLR2/4 gene expression in the lungs of rats with acute lung injury (ALI) complicated by acute hemorrhage necrotizing pancreatitis (AHNP) and the effect of NO on the TLR2/4 gene expression. METHODS: One hundred and ten SD male rats were randomly divided into sham-operated group ( n = 10) , AHNP group (n = 30) , chloroquine-treated group ( n = 30) , and L-Arg-treated group (n =40). The lungs were dissected for lung histological scoring, and bronchoalveolar lavages were harvested for lung injury indexing. TLR2/4 mRNA expression in the lungs was measured by RT-PCR. RESULTS: TLR2/4mRNA was detected in the lungs with low values in the sham-operated group (0.016±0. 210E-2, 0.112 ±0.750E-2) , but it was markedly increased at 3 hours in the AHNP group (0.787±0.751E-2, 1.512 ±1.794E-2) , peaking at 12 hours (1.113 ±6.141E-2, 2.957±2.620E-2; P <0.05 or P <0.01). When lung injuries were aggravated, TNF-α concentrations in the lungs were increased, but NO concentrations were decreased ( P < 0.05 or P < 0.01 ) . When TLR2/4mRNA was inhibited by CQ (3h: 0.313 ± 5.491E-2, 0.005 ±1.419E-3 ; 6h: 0.488 ±7.442E-2, 0.010 ± 1.518E-3; 12h: 0.883 ± 8.911E-2, 0.024 ± 2.760E-3; P< 0.05 or P <0.01) , lung injuries were relieved. NO concentrations in the lungs were increased but TNF-α concentrations were decreased (P <0. 05 or P <0.01). When the rats with AHNP were treated with L-Arg, TLR2/4mRNA expression in the lungs could be effectively inhibited (50mg-T: 0.656 ±3. 977E-2, 1. 501 ±6.111E-2; 100mg-T: 0.260± 0.891E-2, 0.732 ±5.135E-2; 200mg-T: 0.126 ±0.914E-2, 0.414 ± 1.678E-2; 400mg-T: 0.091 ±0.399E-2, 0.287 ± 0.176E-2; P <0.05 or P <0. 01) and lung injuries were relieved. At the same time, NO concentrations in the lungs were markedly increased, but TNF-α concentrations were decreased (P <0.05 or P <0.01). CONCLUSIONS: The expression of TLR2/4mRNA is increased in the lungs in rats with AHNP and lung injuries are aggravated. TLR2/4mRNA gene expression of the lungs of rats with AHNP could be markedly inhibited by NO, leading to the relief of lung injuries.

Chloroquine Relieves Acute Lung Injury in Rats with Acute Hemorrhagic Necrotizing Pancreatitis

Summary： This study preliminarily investigated the mechanism by which chloroquine （CQ） relieves acute lung injury （ALI） complicated in acute hemorrhagic necrotizing pancreatitis （AHNP）. Sixty male Wistar rats were randomized into sham-operated group （group A, n=10）, AHNP group （group B, n=10）, L-arginine-treated group （group C, n=10）, L-N-nitro-L-arginine methyl ester （NAME）-treated group （group D, n=10）, CQ-treated group （group E, n=10） and CQ＋L-NAME-treated group （group F, n=10）. TLR4 expression was measured by using real time-PCR and Western blotting respectively. The results showed that, in the group B, the expression of TLR4 and the levels of TNF-α and IL-6 in the lungs were significantly increased, and the nitric oxide （NO） concentration was reduced, as compared with those in the group A （P〈0.05 or P〈0.01）. Lung injury was aggravated with the increased expression of TLR4. When the inhibitor and stimulator of TLR4, namely L-Arg and L-NAME, were added respectively, lung injury was correspondingly relieved or aggravated （P〈0.05 or P〈0.01）. In the group E, TLR4 expres- sion was substantially lower and NO concentration higher than those in the group B （P〈0.05 or P〈0.01）. However, in the group F, NO concentration was markedly decreased, and the inhibitory effect of CQ on TLR4 expression and the relief of lung injury were weakened when compared with those in the group E （P〈0.05 or P〈0.01）. It was concluded that TLR4 may play an important role in the pathogenesis and development of ALl complicated in AHNP. CQ could relieve ALl by decreasing the TLR4 expression and increasing the NO release.

Clinical Significance of Serum Myelin Basic Proteinin Patients with Severe Acute Pancreatiti

Objective In order to determine serum myelin basic protein (MBP) in patients with severe acute pancreatitis and evaluate its clinical significance. Methods\ Serum MBP was measured in 20 patients with acute hemorrhagic necrotic pancreatitis (AHNP) and in 20 normal subjects by enzyme linked immunoabsorbent assay. Results\ Serum MBP content of AHNP group was significantly higher than that of normal control group (P<0.05). Serum MBP content in patients with pancreatic encephalopathy (PE) was significantly higher than that of those without PE (P<0.05). Conclusion\ ①Serum MBP content in patients with AHNP increased significantly;②Serum MBP content may reflect brain injury and its severity;③The prognosis of AHNP is correlated with its serum MBP content.\;