Effect of ureteral obstruction on matrix metalloproteinase-2 in rat renal cortex

Urinary tract obstruction induces renal damage, including not only interstitial fibrosis but also total loss of tissue integrity in the obstructed kidney. These processes require degradation and remodeling of the extracellular matrix. In the present study, we examined changes in matrix metalloproteinase-2 (MMP-2), a proteolytic enzyme, in a unilateral ureteral obstruction rat kidney model.

Gelatin zymography showed that the both mature and the immature forms of MMP-2 were increased in the obstructed renal cortex. We used real-time reverse transcription polymerase chain reaction (RT-PCR) for the quantification of mRNA expression. MMP-2 mRNA was upregulated in the ligated kidney and peaked on day 3 after obstruction, while, in contrast, MMP-9 mRNA was significantly decreased. Type 1- and type 2-tissue inhibitors of metalloproteinase were increased throughout the experimental period. RT-PCR showed a concomitant increase in the mRNA expression of membrane type-1 MMP (MT1-MMP) and extracellular MMP inducer (EMMPRIN).

We conclude that MMP-2 production in the renal cortex is increased in the early phase of ureteral obstruction and could be involved in the damage induced by ureteral obstruction.