Objective        To determine the effect of bone morphorgenetic protein 7 (BMP7) on insulin secretion in pancreatic beta cells.       Methods       The expression of three type Ⅰ receptors of BMP7

BMPR1A

BMPR1B and ACVR1A

was detected by Western blotting in mouse pancreatic beta cell line MIN6. Then the MIN6 cells were treated respectively by PBS (control)

low-

medium- and high-dose of rhBMP7 (final concentration of rhBMP7 was 10

50

and 100 ng/ml). Then the insulin level of the culture media was detected by ELISA and the intracellular concentration of calcium was determined by laser confocal microscopy.       Results        BMPR1A

BMPR1B and ACVR1A were all expressed in the MIN6 cells. The insulin concentration of PBS

low-

medium- and high-dose rhBMP7 treatment was 0.42±0.11

0.63±0.22

0.82±0.0.19 and 1.24±0.26 ng/（ml·μg）

respectively. The insulin concentration of rhBMP7 treatment groups was significantly higher than that of the control （all P0.05）. In the cells treated by PBS

low-

medium-

and high-dose rhBMP7

the intracellular calcium concentration was increased by (3.5±2.1)%

(4.2±2.3)%

(5.1±3.5)%

and (4.9±2.7)%

respectively. There was no statistical difference in these cells （all P0.05）.       Conclusion       BMP7 enhances insulin secretion significantly in pancreatic beta cells

which may be due to its regulation of calcium-independent exocytosis.