Objective  To investigate the improvement and effect of the method of islet extraction in mice.

  Methods  According to different islet extraction methods, all mice were randomly divided into the common bile duct puncture group (n=100) and common bile duct puncture combined with in situ pancreatic injection group (combined injection group, n=100). Common bile duct puncture combined with in situ pancreatic injection was utilized as the modified method. The islets were selected and purified under stereomicroscope. The morphology and purification of islets were identified. The islet yield and success rate of islet extraction were statistically compared between two groups. The survival of islets after 1 week culture in vitro was analyzed, and the insulin secretion function of islets after 24 h and 4 d culture in vitro was evaluated.

  Results  Compared with the common bile duct puncture group, the islet yield in the combined injection group was significantly increased (P < 0.001). The success rate of islet extraction in both groups was 83% with no statistical significance (P > 0.05). The islets extracted by common bile duct puncture combined with in situ pancreatic injection had intact morphology, high purity and high activity. The survival rate of newly isolated islets was nearly 100% after 24 h culture in vitro. After 1~5 d culture in vitro, the islet cells survived well. After 6 d culture in vitro, the islets showed central death. After culture in vitro for 24 h and 4 d, the islet function of the mice was normal after high glucose stimulation.

  Conclusions  Common bile duct puncture combined with in situ pancreatic injection can increase the islet yield, and the obtained islet cells have high activity and proper function.