摘要
目的:观察慢性应激大鼠结肠黏膜一氧化氮(nitricoxide,NO)的含量变化,探讨NO在慢性应激肠黏膜损伤中的作用及意义.方法:采用慢性束缚应激模型.Wistar大鼠30只,随机分为对照组、应激组、应激+氨基胍组.应激组和应激+氨基胍组大鼠每天置于束缚笼内2h.氨基胍组腹腔注射氨基胍150mg/kg,持续14d处死动物.化学比色法测定肠黏膜组织NO、诱导型NO合成酶(induciblenitricoxidesynthase,iNOS)的含量,组织切片观察肠黏膜炎性细胞浸润情况,电镜观察结肠上皮细胞超微结构的变化.结果:应激组结肠黏膜中NO、iNOS含量高于对照组(NO:47.5±7.9vs32.3±4.7μmol/g,P<0.01;iNOS6.7±1.0vs4.0±0.6nkat/g,P<0.01),中性粒细胞、单核细胞数目增加(N:70±12vs30±6/mm2P<0.01;M:52±9vs26±8/mm2,P<0.01),并出现上皮细胞线粒体肿胀、细胞间紧密连接间隙加大等超微结构的变化.氨基胍组结肠黏膜NO、iNOS含量低于应激组(NO:27.7±12.4vs47.8±7.9μmol/g.P<0.05;iNOS3.8±0.8vs6.7±1.0nkat/g,P<0.01),炎性细胞浸润及超微结构的变化较轻.结论:慢性应激大鼠结肠黏膜NO含量增加,可能参与了应激诱导的肠黏膜损伤.氨基胍对应激诱导的肠黏膜损伤起保护作用.
AIM: To investigate the changes of nitric oxide (NO) in the colonic mucosa of rats submitted to chronic stress and to study the mechanism of chronic stress damage to colonic mucosa. METHODS: Thirty Wistar rats were randomly divided into control group (n =10), stress group (n =10), stress and injection aminoguanidine group (n =10). The latter two groups were submitted to immobilization stress 2 h/d for 14 days. The numbers of the inflammatory cells and ultra structural damage of colon epithelial cells were observed under light and electron microscopes respectively. The concentration of NO and iNOS were measured by chemical methods. RESULTS: The concentrations of NO and iNOS in colonic mucosa of stress group were higher than those in control group (NO: 47.5 ± 7.9vs32.3 ± 4.7 μmol/g, P<0.01; iNOS: 6.7 ± 1.0 vs 4.0 ± 0.6 nkat/g, P<0.01). More neutrophils and mononuclear cells were observed in the stress groupthan in the control group (N: 70 ± 12 vs 30 ± 6 /mm2, P<0.01; M: 52 ± 9 vs 26 ± 8 /mm2, P<0.01). The damage of mitochondria and loosened tight junction were seen in stress group, have concentration of NO and iNOS concentrations were lower in Aminoguanidine group than those in stress group (NO: 27.7 ± 12.4 vs 47.8 ± 7.9 μmol/g, P<0.05; iNOS3.8 ± 0.8 vs 56.7 ± 1.0 nkat/g, P<0.01). Infiltration of inflammatory cells and ultrastructural damage of colon epithelial cells were slighter in aminoguanidine group than those in stress group. CONCLUSION: Chronic stress brought damages to colonic mucosa and nitric oxide might play an important role in these damages while aminoguanidine protected stress-induced colonic mucosa damaged.
出处
《世界华人消化杂志》
CAS
2004年第10期2345-2348,共4页
World Chinese Journal of Digestology
