The Experimental Study Of MMP-2, MMP-9 And α₂M In Severe Acute Pancreatitis

Severe acute pancreatitis is a hazardous disease which sometimes extends rapidly and occurs in 30 of one million people a year.It remains a high level of complications and mortality rate until today.A number of theories about the mechanisms and pathologic changes of SAP have been found in recent years and according to these theories the treatment and prognosis have changed gradually.The clinicians today have pay much more attention to the severity prospection and the extent prevention of SAP.α2M is a major serum protein with diverse functions,including inhibition of protease activity and disease factors.The matrix metalloproteinases are a family of peptidase enzymes responsible for the degration of extracellular matrix components including collagen,gelatin,fibronectin,laminin and proteoglycan.MMP-2 and MMP-9 mainly clear collagen typeⅣ,Ⅴwhich exist in basal memberane of endothelial cell.MMP-2 and MMP-9 are detected absence in most normal conditions contrast to a high presence in pancreatitis.As neutrophils of the inflammatory archetectures express MMPs and many cytokins stimulate the proliferation of nutrophils thus many of these cytokins can facilitate the release of MMPs. MMP-2 and MMP-9 play a important roll in the process of tissue necrosis ,neutrophil transendothelial migration ,circulation disorder and concrescence.In SAP ,considerable correlations about the imbalance of MMP-2,9 and their inhibitor--α2M in the pathologic mechanisms have been detected. MMPs and the inhibitor of them are becoming a new target in the process of therapeutic SAP.Our test is to investigate the effects of MMP-2,9 andα2M in the disorder of microcirculation on SAP and to show another way to prognose or to lessen the pathophysiological process of SAP.Objective To study the expression of MMP-2,9 in pancrease andα2M in serum in rats with SAP, compare the changed feature of pancrease on SAP and the correlation between them.Methods (1) To establish a SAP rat model then observe the wet weight and the pathochange of pancrease. (2) After it is confirmed to establish the SAP model, immunohistochemistry, spectrophotometer were used to detect the expression of MMP-2,9 and ELISA were used to detect the concentra- tion ofα2M in serum.Results 1.Through microscope ,cellular infiltration and necrosis were seen in SAP group. 2. Immunohistochemistry shows: There were highly expressions of MMP-2,9 in SAP group contrast with controls. It cxpressed 100% , 10% in SAP group and controls.Two groups had significantly difference. 3. ELISA: Compared with the control group, the concentration ofα2M in serum of SAP group increased respectively.Conclusions 1.Expressions of MMP-2 and MMP-9 have close relations with the injury of pancrease in SAP, so hasα2M. 2.The detection ofα2M combined with MMP-2 and MMP-9 might be a valuable way in serious prognosis and treatment in SAP.