胰高糖素样肽-1(7-36)NH_2引起的胰岛β细胞内游离钙变化  

Effect of glucagon-like peptide-1(7-36)NH_2 on cytoplasmic free Ca^(2+) in rat pancreatic β cells

作　　者：王毅飞[1] 汪吉仪[2] 王国华[1] 

机构地区：[1]广州军区广州总医院内分泌科,510010 [2]第一军医大学南方医院内分泌科,510515

出　　处：《广东医学》2000年第4期286-288,共3页Guangdong Medical Journal

摘　　要：目的探讨胰高糖素样肽（ＧＬＰ）－１（７－３６）ＮＨ_２促胰岛素分泌的机制。方法以 Ｆｌｕｏ－３为探针，用粘附式细胞仪研究 ＧＬＰ－ １（７－ ３６）ＮＨ_２对培养的新生大鼠胰岛β细胞内游离 Ｃａ^（２＋）浓度的作用。结果在 ２．８ ｍｍｏｌ／Ｌ葡萄糖时，ＧＬＰ－ １（７－ ３６）ＮＨ_２不能使胰岛 β细胞内游离 Ｃａ^（２＋）升高，而优降糖使β细胞内游离 Ｃａ^（２＋）升高明显。在 １６．７ ｍｍｏｌ／Ｌ葡萄糖时，ＧＬＰ－１（７－３６）ＮＨ_２使胰岛β细胞内Ｃａ^（２＋）升高明显，ＥＧＴＡ和硝苯吡啶能完全阻滞ＧＬＰ－１（７－３６）ＮＨ_２引起的Ｃａ^（２＋）升高。结论ＧＬＰ－１（７－３６）ＮＨ_２具有葡萄糖浓度依赖的促胰岛素释放作用，细胞外Ｃａ^（２＋）通过电压依赖性钙通道内流对其引起的β细胞内游离Ｃａ^（２＋）升高起重要作用。Objective To explore the mechanisms by which GLP- l(7 - 36)NH_2 stimulates insulin release. Methods Using adherent cell analysis and sorting cytometer (ACAS) with Fluo - 3 as a probe, effect of glucagon - like peptidc - 1 (7 - 36)NH_2 on cytoplasmic Ca^(2+) concentalion was investigated in cultured neonatal rat pancreatic islst β - Cells. Results In the presence of 2. 8 mmol/ L glucose, GLP - 1 (7 - 36)NH_2 had no effect on cytoplasmic Ca^(2+) in β - Cells, but glybenclamide increased in cytoplasmic Ca^(2)+ in β- Cells. In the presence of 16.7 mmol/L glucose,GLP- l(7 - 36)NH_2 produced a marked increase in cytoplasmic Ca^(2+) in β - cells, which was completely inhibited by EGTA or nifedipine. Conclusion GLP - 1 (7 - 36) NH_2 can stimulate insulin release in a glucose concentration- dependent manner. Inflax of Ca^(2+) through voltage - dependent L - type Ca^(2+) channels plays an important role in increasing cytoplasmic Ca^(2+) in β - cells.

关 键 词：胰岛素 胰岛Β细胞 游离钙 GLP-1(7-36)NH2 

分 类 号：Q578[生物学—生物化学]