Abstract: Objective To investigate the effect of small interference RNA (siRNA) targeting 11β-hydroxysteroid dehydrogenase type 1 on the glucose-stimulated insulin secretion (GSIS) in pancreatic β cell line NIT-1 cell. Methods siRNA plasmid vectors specifically targeting 11β-HSD1 gene were constructed , named as olig886, oligo866 and scrabble control for oligo886, and tansfected into NIT-1 cells. The expression of 11β-HSD1 was detected by RT-PCR and Western blot. Oligo886 vector was transfected into the NIT-1 cells in 25mmol/L glucose concentrations medium .The insulin secretion level was measured in GSIS test. Results After treatment with 11β-HSD1 siRNA, the mRNA levels of 11β-HSD1 in NIT-1 cell were decreased by （78.1±2.9）% and （51.7±2.7）% in olig886 and oligo866 group. The protein of 11β-HSD1 were decreased by（82.2±2.1） % and （56.5±2.0）%. After transfected by olig886 vector, the insulin secretion increased in NIT-1 cell in 25mmol/L glucose concentration medium, contrasting with control group(P＜0.01). Conclusion 11β-HSD1 gene silencing could improve GSIS in NIT-1 cell in . These suggested the 11β-HSD1 regulate local glucocorticoid metabolism in pancreatic islet, therefore, affect the function of insulin secretion.

Key words: RNA interference, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), NIT-1 cell, glucose-stimulated insulin secretion (GSIS)