Influence Of Hyperlipemia On Rats Acute Pancreatitis During Pregnancy

Background:Acute pancreatitis is a potentially lethal disease that is increasing in incidence year by year. Acute pancreatitis and hyperlipimia during pregnancy is a rare but life-threatening condition for both mother and fetus because of its characteristic of urgent morbidity and huge death rate .The etiopathogenisis of hyperlipimia-induce- acute pancreatitis during pregnancy is not distinct , generally,a serum triglyceride (TG) level of more than 1,000 to 2,000 mg/dL in patients with type I, IV, or V hyperlipimia (Fredrickson's classification) can induce acute pancreatitis .There are some reports of acute pancreatitis during pregnancy in clinic ,but there is still few research into the influence of hyperlipemia acute pancreatitis during pregnancy ,and recognition is also quite limited .Therefore ,it is significant to degrade the life-threatening condition for both mother and fetus in clinic through researching influence of hyperlipemia to acute pancreatitis during pregnancy.Objective:To study the influence of hyperlipemia on the acute pancreatitis during pregnancy and its mechanism.Methods:Pregnant Sprague-Dawley rats were randomly divided into the test group(high fat feed)and the control group(balance feed), fed for 16 days separately. Pregnant rats were given intraperitoneal injection with L-arginine for 2 times(the first time is 250mg/100g,the second time is 200 mg/100g.) at an interval of 1 hour. After injection, At the point of 0,12,24 and 48 h, The serum triglyceride(TG),serum amylase(AMS),lypase(LPS) from blood samples and Wet/Dry ratio of pancreas were tested , pancreatic histopathological score based on microscopic changes was evaluated, the expression of TNF-a,Bax and Bcl-2 protein was determined by SP immunochistochemical technique . The data were in MEAN±SD (x±s) and statistics analysis was made by using SPSS 11.5 software for windows.Results: (1) The level of TG in the test group was obvious higher than that of the control group(P<0.05).(2) The serum amylase of the both group peaked at 24 h , but the one of the control group lower than that of the test group obviously(P<0.05).(3) The serum lipse of the test group peaked at 12 h , while the one of the control group peaked at 24 h and lower than that of the test group obviously(P<0.05).(4) Compared with the control group, the Wet/dry ratio of pancreas of the test group increased at 12 and 24 h (P<0.05);(5) The histopathological changes of pancreas in the test group 0 h: hyperemia were seen between lobules ,little inflammatory cells infiltrated; 12 h: hyperemia and edema were seen obviously between lobules , more inflammatory cells infiltrated ; 24 h: the pancreas interstitial edema,inflammatory infiltration,there are bleeding in essence and plenty of vacuolus in acinar cell; 48 h:the pancreas interstitial edema,the structure of lobule diffusely destroyed ,and the pancreas severly filled with hemorrhnge and necrosis,inflammatory infiltration. Compared the control group with the test group, the histopathological changes of pancreas strongly lessened (P<0.05) at 0,12 and 24 hour but it has no statistic meaning at 48 hour(P>0.05).(6) The expression of the TNF-aprotein increased from 0 h to 24 h in both groups . The expression is much higher in the test group than in the control group, there is significant difference between them (P<0.05) at 12 and 24 hour, but there is no difference between them at 0 and 48 hour(P>0.05).(7) The expression of Bax , the test group peaked atl2 h , while the one of the control group peaked at 24 h and lower(P<0.05), both descented to follow times ,but it has no statistic meaning(P>0.05).(8) The expression of Bcl-2 , the test group peaked atl2 h , while the one of the control group peaked at 24 h and lower(P<0.05), both descented to follow times ,but it has no statisticmeaning(P>0.05).Conclusion:Hyperlipemia could make L-Arg-induced-acute-pancreatitis appear ahead of schedule, making the injured more serious. This study demonstrate that hyperlipemia may be a high risk agent of acute pancreatitis during pregnancy ,and the mechanism may be Free Fatty Acid that was released by TG when hyperlipemia and up-regulation of TNF-a expression, Bax and Bcl-2 gene may contribute to pancreatic cell apoptosis and reduce the severity of AP.