[Expression of glycogen synthase kinase-3B in pancreatic tissue of acute edematous pancreatitis rats].

OBJECTIVE

To investigate the expression of apoptosis related gene glycogen synthase kinase-3B (GSK-3B) in acute edematous pancreatitis (AEP), and the relationship between GSK-3B and AEP.

METHODS

The AEP rat model was established by the injection of caerulein [50 microg/(kg x h)] intraperitoneally per hour for 4 times. There were total 36 rats, every 6 rats were sacrificed at 0 h, 1 h, 3 h, 6 h, 12 h and 18 h after the injection of caerulein. Blood samples were taken from portal vein for ELISA examination of pancreatic amylase and lipase, pancreatic mRNA was extracted for RT-PCR analysis of GSK-3B, caspase-3, 9. The expression of GSK-3B protein was examed by Western blot, and acinar cell apoptosis was measured by TUNEL assay.

RESULTS

AEP was successfully induced and pancreatic lesions were most severe at 6 h after the injection of caerulein. Immunohistochemistry assay showed that GSK-3B protein located in cytoplasm of pancreatic acinar cells and endothelial cells, but not in islet cells. The mRNA levels of GSK-3B, caspase-3, 9, the protein level of GSK-3B, as well as cell apoptotic index in AEP rats were significantly increased when compared with the control rats received normal saline. Acinar cell apoptosis index was positively correlated with serum amylase, lipase, ratio of dry/wet of pancreas and GSK-3B mRNA expression, while GSK-3B mRNA level was positively correlated with caspase-3, 9 mRNA expression.

CONCLUSION

The expression levels of GSK-3B mRNA and protein were related to the severity of AEP and acinar cell apoptotic index.