利用Cre/loxP系统构建胰岛α细胞特异性敲除血管紧张素转换酶2基因的小鼠模型

Construction of islets alpha cells specificity knockout mice model of angiotensin-converting enzyme 2 gene by Cre/loxP system

目的构建α细胞特异性血管紧张素转换酶2(ACE2)敲除小鼠模型,为研究胰岛α细胞ACE2功能提供基础。方法利用Cre/loxP系统,将雌性ACE2 loxP/WT与雄性Gcg-cre+/-小鼠进行交配,取鼠尾组织,通过PCR法鉴定子代基因型。选取基因型为ACE2loxP/y Gcg-cre+/-的雄性小鼠为实验所需要构建的模型小鼠(αACE2KO小鼠)。采用免疫荧光和免疫组织化学法检测ACE2表达。采用独立样本t检验。结果免疫荧光分析提示,在Gcg-Cre小鼠胰岛中,(55.14±25.33)%的α细胞表达ACE2,然而αACE2KO小鼠胰岛α细胞中未检测到ACE2表达(t=14.202,P<0.01),同时αACE2KO小鼠的肝、肾、肺、心和骨骼肌中仍然表达ACE2。结论成功利用Cre/loxP原理特异性敲除α细胞ACE2,为研究胰岛局部α细胞ACE2功能提供动物模型和基础。

Objective To construct anα-cell-specific angiotensin-converting enzyme 2(ACE2)knockout mouse model in order to investigate the function of ACE2 inαcells.Methods Female ACE2loxp/WT mice were mated with male Gcg-cre+/-mice.Tail tissue was collected to identify the genotypes of the offspring by polymerase chain reaction.Male offspring with genotype of ACE2loxP/y Gcg-cre+/-were selected(αACE2KO mice).The expression of ACE2 was detected by immunofluorescence and immunohistochemistry.Independent sample t-test was used to analyze the data between the two groups by using SPSS software.The results were expressed as mean±standard deviation.Results In Gcg-Cre mice(control group),(55.14±25.33)%of alpha cells expressed ACE2,while ACE2 was not detected inαcells ofαACE2-KO mice(t=14.202,P<0.01).ACE2 was abundantly expressed in liver,kidney,lung,heart and skeletal muscle.Conclusion We successfully used Cre-loxP system to knock out ACE2 inα-cells of islets,providing an animal model for studying the function of ACE2 in pancreaticα-cells.