Isolation,purification and assessment of rat pancreas islet

【Objective】 This study was conducted to simplify the method of islet isolation and to establish intact islets evaluation system.【Method】 Adult rat pancreatic islets were isolated by type Ⅴ collagenase digestion and purified by Dextran discontinuous density gradient centrifugation.Counting and purity detection of the purified islets were performed under stereoscopic microscopes after staining with Dithizone.The viability of the cultured islets was determined by acridine orange-propidium iodide double-staining.Insulin secretory activity of the islets was detected by glucose challenge tests.A standard islet counting was conducted via Photoshop program by the improved method.【Result】 There were on average(3 840±24) IEQ purified islets isolated from the pancreas of one Sprague Dawley rats.The purity of islets could reach 90%.And the average viability was as high as 92%.【Conclusion】 The islets purified by three-layer Dextran density gradient centrifugation still kept intact structure and functional integrity and were relatively higher in quantity.The counting method based on the Photoshop program simplified the procedures and was more accurate.