Abstract: AIM: To investigate the effect of (Ganoderma lucidum) polysaccharides (Gl-PS) on the insulinreleasing function of pancreatic islets. METHODS: Pancreatic islets were isolated and incubated with 5.6 or 16.7 mmol·L ^-1 glucose and different concentrations of Gl-PS for 1 h.Then the insulin was examined.Verapamil, and verapamil combined EGTA were used to testify whether the insulin-releasing effect of Gl-PS was inhibited by these inhibitors.The effects of Gl-PS on protein expression of the glucose transporter 2(GLUT2) under 5.6 and 16.7 mmol·L ^-1 glucose were also investigated. RESULTS: Gl-PS stimulated the insulin release when incubated with the glucose of 5.6 or 16.7mmol·L ^-1.The insulin releasing effect of Gl-PS was partly inhibited by verapamil and completely inhibited by verapamil +EGTA. Gl-PS could promote the GLUT2 protein expression of pancreatic islets under glucose of 5.6 and 16.7 mmol·L ^-1. CONCLUSION: Gl-PS possesses insulinreleasing effect under the glucose of 5.6 and 16.7 mmol·L ^-1 due to the promotion of the GLUT2 protein expression and the subsequent facilitation of Ca^{2 +} inflow into the pancreatic B cells.

Key words: pharmacology, Ganoderma lucidum polysaccharides, pancreatic islets, insulin-releasing function, glucose transporter 2