A method with high yield for isolation and purification of rat islets

Abstract

Objective To set up an effective and stabile method for isolation and purification of rat islets.Methods Forty-one adult male SD rats weighing 150-380 g were used as organ donors.All donors were divided into 4 groups by body weight.Islets were isolated using digestion at 37℃ by ductal injection of collagenase with sampling timely to determine when to stop digestion,and purified by centrifugation of discontinuous Ficoll density gradient.The identification of purified islets was evaluated by dithizone staining.The viability of islet was assessed by fluorescence staining of aridine orange and propidium iodide.The function of purified islets was determined by glucose-stimulated insulin release test.Results The total number of purified islets in one pancreas was 1056 ± 357.There was no significant difference among the islet yields of the 4 groups with different body weight (for groups A,B,C and D:932 ± 542,1036 ± 339,1142±305,and 1108 ± 178,respectively,P ＞0.05).The purity of islets was more than 90％.The viability of islets was more than 90％.The simulation index was 2.08 ± 0.10.Conclusion Using the modified method,the islet isolated and purified from rats with different weight had stable high yield,high purity,high viability and good function. Key words: Islet ; Isolation ; Purification; Rat