Abstract: Objective By establishing mouse model of pancreatic injury and regeneration and employing whole genome gene chip technology, to identify regenerating islet-derived 3 alpha（Reg3α）gene whose expression was elevated in pancreatic regenerating models, hence further investigate the regulatory role of Reg3α in pancreatic regeneration by over expression of Reg3α gene in pancreatic endothelial cells (MS1). Methods Mouse model of partial (90%) pancreas removal was established by panceatectomy. Blood glucose levels were tested before and 12hr, 24hr after pancreatectomy, respectively. The remaining pancreas tissues were collected 48h post pancreatectomy. Elevated expression of Reg3α gene was identified by gene chip analysis and verified by q-PCR. The gene was then cloned in an expression plasmid and expressed in MS1 cells in culture. Insulin levels in culture media of the transfected cells were detected by ELISA 48h after cell transfection. The mRNA levels of Pdx1 and Insulin2 genes in transfected cells were tested by q-PCR. Results Comparing untransfected group with vector (PcDNA3.1)-transfected group，no significant change of insulin levels in MS1 culture media was observed（14.63±6.88，P＞0.05）；when comparing Reg3α over expression group with untransfected and vector-transfected groups, significant increases in insulin levels were observed, 193.43±7.09 (P＜0.01） over untransfected group, and 208.07±5.52 ( P＜0.01） over vector-transfected group, respectively. Again, comparing with untransfected and vector-transfected groups, Reg3α over expression group expressed significantly higher mRNA levels of Pdx1 and Insulin2 genes（P＜0.01）. Conclusion Over expression of Reg3α gene in MS1 cells can elevate the expression of Pdx1 and Insulin2 in mRNA levels, and increase insulin secretion. Reg3α promote endothelial cell expression and secretion of insulin ,which may have a compensatory role in β-cell function.

Key words: Reg3α, MS1 Cells, Insulin, Transfection