mRNA expression of chemokines in rat kidneys with ureteral obstruction

(Backgrounds) It has been demonstrated that leukocyte infiltration, mainly of macrophages and lymphocytes, into obstructed kidneys (OBK) of rats during unilateral ureteral obstruction (UUO). Chemokines (C-C subfamily) may be involved in this mechanisms. Thus, we accessed the gene expression of chemokines in renal cortex of rats with UUO. (Materials and methods) Female SD rats were sacrificed at various time points after UUO. mRNA expression of MCP-1, RANTES and MIP-1α was determined by semi-quantitative RT-PCR. (Results) Control kidneys (CNK) showed a weak mRNA expression of MCP-1, RANTES and MIP-1α. OBKs showed an increase in MCP-1 at 2 hours of UUO and a significant increase at 4 hours of UUO as compared with CNKs or contralateral unobstructed kidneys (CLK). The mRNA levels of RANTES and MIP-1α were not increased until 72 hours of UUO in CLKs or OBKs. There were slight, but significant, differences of RANTES and MIP-1α expression between OBKs and CNKs at 120 hours of UUO. (Conclusions) We suggest that the early increase in MCP-1 contributes to the leukocyte infiltration and that RANTES and MIP-1α plays a partial role in a late increases.