论文部分内容阅读
目的探讨葡萄糖刺激下小鼠胰岛素的动态分泌及胰岛素囊泡的分布变化。方法雄性C57BL小鼠50只,处死后分离小鼠胰岛,采用免疫荧光法孵育,镜下观察小鼠胰岛β细胞分布情况;取50个胰岛在含2.8mmol/L及16.7mmol/L葡萄糖的低糖和高糖KRBH缓冲液中灌流,采用放射免疫法分析胰岛素的动态分泌;另取60个胰岛分为低糖组与高糖组各30个,分别采用低糖和高糖KRBH缓冲液孵育5min,电镜下观察2组胰岛素分泌囊泡密度、分布及未成熟囊泡情况。结果小鼠胰岛β细胞位于胰岛中央;胰岛素第1时相分泌呈典型峰状,AUC为4.924±0.536,第2时相分泌呈平台样均匀分泌,AUC为11.180±0.690;低糖组胰岛素囊泡密度、距离β细胞膜>50~300nm、>300nm胰岛素分泌囊泡密度和未成熟胰岛素分泌囊泡密度((213.3±10.2)、(41.4±1.96)、(152.4±9.52)、(2.9±0.21)个/0.1μm2)明显低于高糖组((249.7±4.2)、(58.9±2.6)、(172.7±4.99)、(6.04±0.98)个/0.1μm2)(P<0.05),距离β细胞膜<50nm胰岛素分泌囊泡密度((19.6±0.7)个/0.1μm2)与高糖组((18.1±0.94)个/0.1μm2)比较差异无统计学意义(P>0.05)。结论葡萄糖刺激下的小鼠胰岛素第1时相分泌呈典型峰状,第2时相分泌呈平台样分泌;高糖刺激5min,胰岛素分泌囊泡合成增多,其中锚定囊泡分布无明显增多,但可释放池囊泡及储备池囊泡明显增多。
Objective To investigate the changes of insulin secretion and insulin vesicles in mice stimulated by glucose. Methods Fifty male C57BL mice were sacrificed and the islets were isolated from mice. Immunofluorescence staining was used to observe the distribution of islet β cells in mice. Fifty islets were cultured in low glucose (2.8 mmol / L) and glucose (16.7 mmol / L) And high glucose KRBH buffer. The dynamic secretion of insulin was analyzed by radioimmunoassay. Another 60 islets were divided into 30 low glucose and high glucose groups and incubated in low and high glucose KRBH buffer for 5 min. The density, distribution and immature vesicles of insulin secreting vesicles in 2 groups were observed. Results The pancreatic islet β cells were located in the central part of the islets. The first phase of insulin secretion showed a typical peak with AUC of 4.924 ± 0.536. The second phase of the secretion was plateau-like and the AUC was 11.180 ± 0.690. The insulin density (213.3 ± 10.2), (41.4 ± 1.96), (152.4 ± 9.52) and (2.9 ± 0.21) / (3), respectively. 0.1μm2) was significantly lower than that of high glucose group (249.7 ± 4.2), (58.9 ± 2.6), (172.7 ± 4.99), (6.04 ± 0.98) /0.1μm2) (P <0.05) The density of secretory vesicles (19.6 ± 0.7) /0.1μm2) was not significantly different from that in high glucose group (18.1 ± 0.94) /0.1μm2) (P> 0.05). Conclusions Glucose-stimulated mouse insulin phase 1 showed typical peak shape, and the second phase showed plateau-like secretion. After high glucose stimulation for 5 min, the synthesis of insulin-secreting vesicles increased, but the distribution of anchored vesicles did not increase significantly. However, the number of vesicles in reservoirs and reservoirs in reservoirs increased significantly.