Effect of acidizing pretreatment in respiratory acidosis on neutrophil inflammatory infiltration in ischemic-reperfusion injury
10.11855/j.issn.0577-7402.2019.10.06
- Author:
Liang-chao QU
1
Author Information
1. Department of Anesthesiology, First Affiliated Hospital of Nanchang University
- Publication Type:Journal Article
- Keywords:
Ischemia-reperfusion lung injury;
Neutrophil;
Pretreatment;
Respiratory acidosis
- From:
Medical Journal of Chinese People's Liberation Army
2019;44(10):843-850
- CountryChina
- Language:Chinese
-
Abstract:
[Abstracts] Objective To investigate the effect and mechanism of acidizing pretreatment in respiratory acidosis on ischemia-reperfusion (IR) lung injury in rats. Methods Forty-eight male Sprague-Dawley rats, weighted 250-300 g, were randomly divided into 6 groups (8 each). Rats in control group: the left pulmonary hilum was dissociated without occlusion; in sham group: the respiratory rate was adjusted to maintain the partial pressure of end-tidal carbon dioxide reached 56-65 mmHg for 5 min, the left hilar not blocked; in IR group: the left pulmonary hilum was occluded for 45 min followed by reperfusion for 180 min; in group APC: done as in sham group and blocked the left hilar as in group IR; in group SB+IR: MMP-9 inhibitor SB-3CT 5 mg/kg was intraperitoneally injected, and then treated as in group IR 30 min after; in group SB+APC: done as in group APC, and then SB-3CT 5 mg/kg was injected 30 min after. Rats in all the 6 groups were sacrificed by arterial bleeding when the experiments ended, and lung tissues were taken. HE staining was performed to observe the pathological changes of lung tissues, and immunohistochemistry was used to detect the infiltration of neutrophils (PMN) in lung tissue. Western blotting was used to detect the expression of NF-κB and MMP-9 proteins. Immunofluorescence staining was used to detect the co-expression of NF-κB and MMP-9 proteins. Results Statistically significant differences existed in each group (P<0.05) in the pathological scores of lung tissue (group control 3.18±1.21; sham group 3.18±1.30; group IR 13.85±5.62; group APC 9.77±3.96; group SB+IR 5.11±2.53; group SB+APC 5.01±2.17), PMN infiltration (IOD values of each group were: group control 0.0015±0.0005; group sham 0.0014±0.0006; group IR 0.0076±0.0012; group APC 0.0057±0.0017; group SB+IR 0.0035±0.001; group SB+APC 0.0031±0.0011), NF-κB and MMP-9 protein expression levels (relative expression values of each group were: control group 0.14±0.04, 0.24±0.07; group sham 015±0.03, 0.25±0.06; group IR 0.56±0.09, 1.09±0.17; group APC 0.41±0.11, 0.81±0.11; group SB+IR 0.36±0.08, 0.56±0.11; group SB+APC 0.35±0.09, 0.55±0.10), and the co-expression of NF-κB and MMP-9 proteins. Multiple comparison results of the above indicators between groups displayed that no significant difference existed between group sham andl group contro (P>0.05). The above indicators were significantly higher in group IR, group APC, group SB+IR and group SB+APC than those in control group and sham group (P<0.05); and were significantly lower in group APC, group SB+IR and group SB+APC than that in group IR (P<0.05); and were significantly lower in group SB+IR and group SB+APC than that in group APC (P<0.05); and no significant difference was found between group SB+APC and group SB+IR (P>0.05). Conclusions In the IR rat model, acidizing pretreatment in respiratory acidosis can alleviate PMN infiltration and IR lung injury. The mechanism may be related to inhibition of NF-κB/MMP-9 protein expression.
