乌司他丁对脓毒症大鼠胰腺外分泌功能的保护作用及机制研究

Protective effect of ulinastatin on pancreatic exocrine function in rats with sepsis and related mechanisms

目的研究脓毒症时大鼠胰腺外分泌功能的损伤机制,并探讨乌司他丁对脓毒症所致胰腺外分泌功能损伤的保护效应。方法 SPF级雄性大鼠30只,按随机数字表法分为对照组、LPS组和UTI组,每组各10只。LPS组腹腔内注射LPS 15 mg/kg建立脓毒症模型,UTI组在腹腔内注射LPS后立即按照50 000 U/kg注射UTI,LPS组、对照组均注射等量的生理盐水。12 h后留取大鼠血标本,用自动生化仪检测血清淀粉酶、脂肪酶,用酶联免疫吸附试验(ELISA)检测TNF-α;取胰腺组织,H-E染色观察胰腺形态学变化,TUNEL法计数凋亡细胞,Western印迹法检测凋亡因子Cyt C、Caspase3、Bcl-2、Bax基因表达水平。结果 LPS组、UTI组血清淀粉酶、脂肪酶、TNF-α均显著高于对照组(P<0.01),UTI组显著低于LPS组(P<0.01)。对照组、LPS组、UTI组胰腺组织H-E染色改良Schmidt评分分别为0、5.13和3.70分,UTI组显著低于LPS组(P<0.01)。凋亡细胞指数LPS组显著高于对照组(P<0.01),UTI组显著低于LPS组(P<0.01)。Bax、Cyt C、Caspase3表达,LPS组显著高于对照组,UTI组显著低于LPS组。Bcl-2表达,LPS组显著低于对照组,UTI组显著高于LPS组。结论 LPS诱导的脓毒症大鼠存在胰腺外分泌功能损伤;乌司他丁可以保护脓毒症大鼠胰腺外分泌功能,抑制脓毒症时的细胞凋亡可能为其保护机制之一。

Objective To investigate the effect of ulinastatin on pancreatic exocrine function in rats with sepsis and related mechanisms. Methods Thirty male SPF rats were randomly divided into control group,LPS group and UTI group with 10 animals in each group. The sepsis model was induced by intraperitoneal injection of LPS（ 15 mg/kg）. Intraperitoneal injection of ulinastatin（ 50 000 U/kg） was given to rats in UTI group when sepsis model was established,while same volume of normal saline was given to rats in LPS group and control group. Blood samples were collected 12 h after sepsis model was made,and the level of amylase and lipase were determined by automatic biochemical analyzer,TNF-α was determined by enzyme-linked immunosorbent assay（ ELISA）. The morphological changes of pancreas tissue were observed by H-E staining. The apoptosis of acinar cells was determined by terminal deoxynucleotidyl transferase-mediated nick end labeling（ TUNEL） assay. The expression of apoptosis factors（ Cyt C,Caspase3,Bcl-2 and Bax） were determined by Western blotting. Results Serum amylase,lipase and TNF-α levels in LPS group and UTI group were significantly higher than those in control group（ P〈0. 01）,while the levels in UTI group was significantly lower than those in LPS group（ P〈0. 01）. The H-E staining of pancreatic tissue showed that the modified Schmidt scores of control group,LPS group and UTI group were0,5. 13 and 3. 70 respectively（ P〈0. 01）. The apoptosis index in LPS group was significantly higher than that in control group（ P〈0. 01）,the index in UTI group was significantly lower than that in LPS group（ P〈0. 01）. The expressions of Cyt C,Caspase3 and BAX in LPS group were significantly higher than that in control group,the expressions in UTI group were significantly lower than that in LPS group; while the expression of Bcl-2 in LPS group was significantly lower than that in control group,the expression in UTI group was significantly higher than that in LPS group. Conclusion Pancreatic exocrine function is damaged in septic rats induced by LPS. Ulinastatin can protect the pancreatic exocrine function in rats with sepsis,which is associated with the inhibition of apoptosis.