1型糖尿病大鼠模型的制备及建模失败后补救措施与效果

Establishment of type 1 diabetic rat models and effect of remedial measures for failed model

目的:研究通过链脲佐菌素(Streptozotocin,STZ)诱导建立1型糖尿病大鼠模型的方法及首次建模失败后的补救措施及效果。方法:健康6-8周龄雄性Wistar大鼠30只,随机分为2组,建模组25只,非建模组5只。给予建模组大鼠一次性大剂量腹腔注射STZ(65mg/kg),同时对非建模组大鼠腹腔注射相同体积的柠檬酸缓冲液。72h后检测大鼠的血糖值判断建模是否成功。对首次建模失败的大鼠常规饲养一周,再次腹腔注射STZ(65mg/k g),观察其成模状况。分别在建模后第0、2、4、6、8周测量大鼠的体重与血糖并观察其一般情况。于第8周处死全部大鼠,取胰腺标本进行HE染色和胰岛素的免疫组化染色,观察胰腺组织的病理学改变。结果:建模组有21只大鼠首次注射STZ 72h后,血糖值达到成模标准,4只血糖值未达到成模标准,再次注射STZ72h后血糖值检测均达到成模标准。持续观察8周,首次建模成功及补救建模组大鼠均成模稳定,糖尿病症状明显,未见血糖转复正常。非建模组大鼠各项指标均未见异常。与非建模组相比,首次建模成功组及补救组大鼠胰岛形态不规则,体积萎缩变小,胰岛内分泌细胞数量明显减少。胰岛素胰腺免疫组化检测发现,与非建模组相比,首次建模成功组和补救组胰岛素分布面积显著减少。结论:一次性大剂量腹腔注射STZ可制备有效、稳定的1型糖尿病大鼠模型。首次建模失败后,适时再次注射STZ仍可制备高质量的1型糖尿病大鼠模型。

Objective： To establish type 1 diabetic rat models by intraperitoneal injection of streptozotocin and observe the stability of diabetic changes in rats and the remedial measures for failed modeling rats and their results. Methods： 30 male Wistar rats（6~8-week-old） were randomly divided into 2 groups, including experiment [EG, n=25, 65 mg/kg of STZ, single i.p.] group and control [CG, n=5, citrate buffer solution i.p.] group. 72 h after injection with STZ, the blood glucose levels（BGLs） were evaluated to verify whether the type 1 diabetic rat model was established. The failed modeling rats were normally fed for 1 week before the second intraperitoneal injection（65 mg/kg）. Overt behavior, body weights and levels of blood glucose were evaluated at the 0^（th）, 2^（nd）, 4!（th）, 6^（th）, 8thweek respectively. All rats were executed at the 8thweek to collect the samples of pancreas. HE staining and immunohistochemical staining of insulin were used to evaluate the pathological changes. Results： 72 h after injection of STZ, 21 diabetic models were established out of 25 rats. After a second injection,4 failed modeling rats were successfully remodeled. Compared with control group, the pancreatic islets of diabetic rats were irregular and shrunk, and the endocrine cells of pancreatic islets were markedly decreased in experiment rats. In immunohistochemical detection of pancreatic of insulin, compared with control group, insulin distribution area of diabetic rats significantly reduced. Conclusion： With the dose of 65 mg/kg of STZ intraperitoneal injection, type 1 diabetic rat models can be established with obvious symptoms and without conversion. By reinjection at the right moment, 4 failed modeling rats were successfully remodeled.