基质金属蛋白酶对新生鼠窒息后心肌重塑的影响

目的探讨新生鼠窒息后心肌组织基质金属蛋白酶(MMPs)表达对心肌重塑的影响。方法将7~10日龄Wistar小鼠60只,随机分成窒息A、B、C 3组(分别为窒息复氧后1、7、14 d,各组15只)、对照组(D组,n=15)。模拟新生鼠常压窒息模型。免疫组织化学法测定心肌组织MMP-3、MMP-9活性;氯胺T法测定心肌胶原水平。结果心肌组织MMP-3活性为一过性增高,以B组最高(P<0.05),且MMP-3活性表达早于MMP-9;MMP-9活性窒息后逐渐增高(P<0.05);心肌胶原水平窒息后逐渐增高,d14时最高;MMP-3、MMP-9与胶原水平呈正相关(r=0.482,0.679 P均<0.05)。结论新生鼠窒息后心肌MMP-3、MMP-9激活,继发胶原水平增高,可能是导致心肌间质重塑的因素之一。

Influence of Matrix Metalloproteinase on Myocardial Remodeling in Neonatal Rats after Asphyxia

Objective To explore the influence of matrix metalloproteinase(MMPs) on myocardial remodeling of asphyxiated neonatal rats.Methods Sixty neonatal Wistar rats 7 to 10 days old were randomly divided into 4 groups:control group(group D,n=15);asphyxia groups(group A,B and C,1,7,14 days after asphyxia,n=15).Animal model was reproduced by normobaric asphyxia.The(myo-)cardial MMP-3,9 activities were measured by immunohistochemical assay.The quantity of myocardial collagen was measured by chloramines T.Results MMP-3 activities in group A,B,C were significantly higher than that of group D, reaching a peak on group B((P<)0.05).The activity of MMP-3 increased earlier than that of MMP-9.The MMP-9 activity gradually increased after asphyxia,and was higher than that in group D(P<0.05).The amount of myocardial collagen was not significantly different in group A and D((P>)0.05).However,the amount of myocardial collagen in group B and C were significantly greater than that in group D(P<0.05),and group C was the highest.MMP-3 and MMP-9 activities were positively correlated with myocardial collagen(r=0.482,0.679 all(P<)0.05).Conclusions The MMPs activities are actiated after asphyxia and related to the increasing of myocardial collagen.Possibly MMPs can lead to myocardial remodeling.