内源性CO在CCK-8减轻脂多糖所致的急性肺损伤中的作用

目的：探讨内源性一氧化碳（CO）在八肽胆囊收缩素（CCK-8）减轻LPS所致急性肺损伤（ALI）中的作用。 方法： 将56只大鼠随机分为正常对照组、LPS组、LPS+ZnPP（HO-1特异性阻断剂）组、LPS+Hm（CO供体）组、CCK-8+LPS组、CCK-8+LPS+ZnPP组、CCK-8组7组，每组8只。各组给药后2 h，6 h，12 h行支气管肺泡灌洗、检测支气管肺泡灌洗液（BALF）中中性粒细胞（PMN）数目，并进行肺组织的形态学观察；计算大鼠死亡率；测定肺组织中MDA、CO含量。 结果： 给药2 h和6 h后，各组大鼠死亡率均为0，LPS 注入12 h后大鼠死亡率高于相应对照组，LPS+Hm和CCK-8+LPS组大鼠死亡率均低于LPS组，LPS+ZnPP和CCK-8+LPS+ZnPP组大鼠死亡率分别高于LPS和CCK-8+LPS组；LPS组肺组织均出现损伤变化，同时BALF中PMN数目和肺组织中MDA和CO含量高于相应对照组；LPS+Hm和CCK-8+LPS组肺组织损伤程度、BALF中PMN数目和肺组织中MDA含量低于相应LPS组，但肺组织中CO含量高于相应LPS组；LPS+ZnPP和CCK-8+LPS+ZnPP组肺组织损伤程度、BALF中PMN数目和肺组织中MDA含量分别高于相应LPS和CCK-8+LPS组，而肺组织中CO含量分别低于相应LPS组和CCK-8+LPS组。 结论： CCK-8可通过内源性CO介导的抗氧化、抑制PMN聚集等效应来发挥改善LPS所致的肺损伤作用。

Role of carbon monoxide in CCK-8 ameliorating acute lung injury induced by LPS

AIM: To study the role of carbon monoxide (CO) in the mechanism of cholecystokinin-octapeptide (CCK-8) for attenuation of acute lung injury (ALI) induced by lipopolysaccharide (LPS). METHODS: Fifty-six adult male rats were randomly divided into seven groups: control group, LPS group, LPS ZnPP (a specific inhibitor of HO-1) group, LPS Hemin (Hm, CO donor) group, CCK-8 LPS group, CCK-8 LPS ZnPP group and CCK-8 group (n=8 for each). Bronchoalveolar lavage was performed 2 h, 6 h and 12 h respectively after treatments. The numbers of polymorphonuclear leukocytes (PMN) in bronchoalveolar lavage fluid (BALF) was detected. The mortality of rats and the structure of lung tissues were observed. MDA and CO contents in lung tissues were also measured. RESULTS: The mortalities of rats were both zero 2 h and 6 h after agent administration. The mortality of rats was higher than control group 12 h after LPS administration. The mortality of rats in LPS Hm and CCK-8 LPS group were lower than that in LPS group, and its in LPS ZnPP and CCK-8 LPS ZnPP group were lower than that in LPS and CCK-8 LPS group, respectively. Lung injury was observed in LPS group. At the same time the number of PMN, MDA and CO content were higher than those in control group. The degree of lung injury, PMN numbers and MDA content were lower, while CO content in LPS Hm and CCK-8 LPS group were higher than those in LPS group. However, the degree of lung injury, PMN number and MDA content were higher, CO content were lower in LPS ZnPP and CCK-8 LPS ZnPP group than those in LPS and CCK-8 LPS group, respectively. CONCLUSION: CCK-8 attenuates the LPS-induced acute lunginjury by means of anti-oxidation and inhibition of PMN aggregation, which are both mediated by CO.