Experimental Study Of Changes In Cell Apoptosis And Expression Of Fas/FasL In Acute Pancreatitis

Objective: To study the relationship between the pancreatic cell apoptosis and the severity in rats with acute pancreatitis(AP),and to detect the expression of Fas/FasL system and its role in apoptosis.Methods: 30 healthy S.D rats were divided into three groups:AEP group,ANP group and control group,each group had 10 rats.The models of acute edematous pancreatitis(AEP) and acute necrotizing pancreatitis(ANP) were established by retrograde injection of different concentration of sodium deoxycholate into the common bile-pancreatic duct.Cell apoptosis in AP was analysed by TUNEL, and the expression of Fas/FasL protein was detected by immunohistochemical method.Result: After 6 hours of models completed,the histological changes of acute pancreatitis had occurred in groups of AEP and ANP,and the pathologic score,serum mylase,volumes of ascites were higher in AEP group than ANP group.Normal pancreatic tissue had rare apoptotic cells and it was increased in acute pancreatitisThe apoptosis index(AI) was higher in AEP group than in ANP group(P<0.05). immuno-staining revealed that moderate to strong FasL irnmunoreactivity was present in acini of all groups.The expression of Fas protein wasn't detected in the normal pancreas.In AP,Fas irnmunoreactivity was present in areas of inflammatory infiltration, and its expression was in correspondence with the AI and negatively related to the degree of AP.Conclusion: In AP,pancreatic tissue can express Fas protein.Through the Fas receptor the activation of apoptosis may be a beneficial response to tissue injury in AP.