摘要
目的探讨预防性和治疗性给予果糖二磷酸钠镁(Na+-Mg2+-FDP)对于链脲佐菌素(streptozotocin,STZ)损伤的胰岛B细胞有无保护作用。方法应用葡萄糖氧化酶法测定血糖、放免法测定血清胰岛素、免疫组化S-P法计数A、B、D细胞分别表达胰高血糖素、胰岛素、生长抑素的阳性胰岛个数,并在HE染色光镜下观察胰岛形态改变。统计方法采用方差分析,q检验及直线相关分析。结果①保护组能有效降低血糖,升高胰岛素。而治疗组与STZ损伤组血糖一直维持在高水平,胰岛素持续处于低水平,保护组与治疗组、STZ组分别比较,血糖及胰岛素均有显著性差异(P<0.01)。②HE光镜下观察治疗组与STZ组相似胰岛萎缩,总数量减少,大部分胰岛细胞完全融合,出现玻璃样变性,核溶解。保护组胰岛结构尚完整,细胞变性程度较轻,接近于正常胰岛形态。③免疫组化S-P法观察治疗组与STZ组相似,B细胞表达胰岛素量显著减少,而A细胞表达胰高血糖素量、D细胞表达生长抑素量增多,尤以A细胞增多显著。两组间差异无统计性意义(P>0.05)。而保护组B细胞表达胰岛素量、A细胞表达胰高血糖素及D细胞表达生长抑素的程度接近正常,分别与STZ组、治疗组比较,差异均有统计学意义(P<0.01,P<0.05)。结论预防性给予果糖二磷酸钠镁对STZ诱导胰岛B细胞损伤具有明显的保护作用。而治疗性给予果糖二磷酸钠镁对STZ所致的胰岛B细胞结构损伤无治疗作用。STZ是诱导大鼠糖尿病形成的主要原因,而A细胞胰高血糖素表达程度增强以及D细胞生长抑素表达量增多可能也与大鼠糖尿病的形成有一定关系。
Objective To explore whether sodium and magnesium saline of fructose-1, 6-diphosphate （ Na^＋-Mg^2＋-FDP） protects B cells in islet of Langerhans injured by streptozotocin （STZ）. Methods Healthy adult male Wistar rats were randomly divided into five groups ： STZ group （ receiving once 2% STZ in citric acid solution at dose of 60 mg/kg） , blank control group （receiving citric acid solution） , FDP group （treated as STZ group, plus Na^＋-Mg^2＋-FDP solution twice a day at total dose of 500 mg · kg^-1· d^-1 for 15 d）, protected group （ receiving Na^＋ -Mg^2＋ -FDP solution at 500 mg/kg first, then 2% STZ in citric acid solution at dose of 60 mg/kg once, Na^＋-Mg^2＋-FDP solution twice a day at total dose of 500 mg· kg^-1· d^-1 for 15 d ） , treated group （48 h after receiving 2% STZ in citric acid solution at dose of 60 mg/kg, starting Na^＋ -Mg^2＋ -FDP solution twice a day at total dose of 500 mg · kg^-1 · d^-1 for 15 d）. On the 15^th day after experiment starting, all rats were killed and the end of pancreatic gland was prepared for following experiments. Blood glucose by using glucose oxidase kit and serum insulin by radioimmunoassay was determined. The number of positive islets of which A, B and D cells expressed glucagons, insulin and somatostatin was counted by S-P immunohistochemistry. The morphology of islet of Langerhans stained by HE was observed under optical microscope. Statistical significance was determined by q test and X^2 test, the related coefficient was determined by rectilinear correlation analysis （α =0.05）. Results The blood glucose dropped and serum insulin rose in protected group, but the glucose in treated group and STZ group maintained at high level, and serum insulin maintained at low level. The blood glucose and insulin of the protected group showed significant differences with that of the treated group and STZ group respectively （P 〈 0. 001 ）. The alteration of blood glucose and insulin showed negative rectilinear correlation. In STZ group and treated group, islets shrank, the number of islets decreased, islet cells in large part fused completely and appeared glass-like denaturation, and the cellular nucleus appeared dissolving phenomenon. But in protected group, the intact architecture of islet, and very light cellular denaturation was observed. The amount of expressing insulin in B cells decreased significantly in STZ group and treated group, and that of expressing glucagons in A cells increased more evidently than that of somatostatin in D cells, and there was no statistical difference between the two groups （P 〉 0. 05）. However, the expressions of insulin, glucagons and somatostatin were close to normal level in protected group, which were of statistical significance with that of STZ group and treated group （ P 〈 0.01 and P 〈 0. 05）. Conclusion Preventive application of FDP has a protective effect on B cells of islets from the damaged structure induced by STZ. Therapeutical application of FDP can not protect B cells against destroyed structure. The reason of diabetes occurrence is that B cells are damaged and the insulin reduces. Besides, the increased expression of glucagons and somatostatin may be correlated closely with diabetes development.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2006年第24期2451-2455,共5页
Journal of Third Military Medical University
关键词
1
6二磷酸果糖
链佐菌素
胰岛
细胞损伤
细胞保护
fructose-1,6-diphosphate
streptozotocin
islet of Langerhans
cell injury
cytoprotection
作者简介
彭东红（1968-），女，四川省南充市人，博士研究生，主治医师，讲师，主要从事哮喘免疫机制方面的研究。电话：13527561968
