Ravier Magalie A, Rutter Guy A
Division of Medicine, Department of Cell Biology, Imperial College, South Kensington, London SW7 2AZ, UK.
Methods Mol Biol. 2010;633:171-84. doi: 10.1007/978-1-59745-019-5_12.
The endocrine pancreas contains small clusters of 1,000-2,000 neuroendocrine cells termed islets of Langerhans. By secreting insulin, glucagon, or other hormones as circumstances dictate, islets play a central role in the control of glucose homeostasis in mammals. Islets are dispersed throughout the exocrine tissue and comprise only 1-2% of the volume of the whole organ; human pancreas contains about 10(6) islets whereas rodents have approximately 2 x 10(3) islets. The isolation of islets from the exocrine tissue usually begins with digestion of the pancreas with collagenase. Collagenase-containing medium is either injected into the pancreatic duct, and the organ left to digest in situ, or added after isolation of the pancreas and its dissection into small pieces ex vivo. Islets can then be separated from the exocrine tissue by gradient density or by handpicking. The islets obtained can either be used intact, for example, to measure insulin or glucagon secretion or be dispersed into single cells with a Ca(2+)-free medium or with trypsin/dispase. The latter facilitates the introduction of recombinant or trappable probes and microimaging studies of, for example, changes in cytosolic-free Ca(2+) concentration or the dynamics of individual organelles or proteins.
内分泌胰腺包含由1000 - 2000个神经内分泌细胞组成的小细胞团，称为胰岛。胰岛可根据具体情况分泌胰岛素、胰高血糖素或其他激素，在哺乳动物的葡萄糖稳态控制中发挥核心作用。胰岛分散于整个外分泌组织中，仅占整个器官体积的1 - 2%；人类胰腺约含10⁶个胰岛，而啮齿动物约有2×10³个胰岛。从外分泌组织中分离胰岛通常始于用胶原酶消化胰腺。含胶原酶的培养基可注入胰管，让器官在原位消化，也可在分离胰腺并将其切成小块后在体外添加。然后可通过密度梯度法或手工挑选从外分泌组织中分离出胰岛。获得的胰岛既可以完整使用，例如用于测量胰岛素或胰高血糖素的分泌，也可以用无钙培养基或胰蛋白酶/分散酶分散成单个细胞。后者便于引入重组或可捕获的探针，以及进行例如胞质游离钙浓度变化或单个细胞器或蛋白质动态变化的显微成像研究。
