Expression and significance of MMP9 and TIMP1 in traumatic brain edema of rats

Objective To explore the expression and significance of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in traumatic brain edema of rats. Methods The moderate trau-matic brain edema models were established according to Feeney's method. Dry-wet weight method was used to detect the BWC, the expression of MMP9 and TIMP1 mRNA was examined by RT-PCR technique, and the ratio of MMP9 mRNA/TIMP1 mRNA was analyzed also. Results The brain water content,the ex-pression levels of M MP9 and TIMP1 mRNA, and the ratio of MMP9 mRNA/TIMP1mRNA in experimental group were all higher than those in control groups (all P<0.05). Meanwhile, there was a positive correla-tion between the expression of MMP9 and TIMP1 mRNA,the ratio of MMP9 mRNA/TIMP1 mRNA,and BWC (r=0.654 and 0.355 respectively, P<0.05). Conclusion The imbalance of MMP9 and TIMP1 might play key roles in the process of the traumatic brain edema of rats. Key words: Brain edema;  Matrix metalloproteinase 9;  Tissue inhibitor of metalloproteinase 1