Transient and sequential expression of chemokine mRNA in glomeruli in puromycin aminonucleoside nephrosis.

Chemokines are a large family of low-molecular-weight proinflammatory cytokines that stimulate recruitment of leukocytes. We previously reported that among six chemokines, the expression of mRNAs for MCP-1, MCP-3, TCA3, and MIP-1alpha, but not for MIP-1beta and RANTES, was markedly elevated in the renal cortex of rats with puromycin aminonucleoside induced nephrosis. In this study we have determined the glomerular expression of the chemokine mRNAs in this model using quantitative competitive reverse-transcriptase polymerase chain reaction. After an injection of puromycin aminonucleoside, the number of monocytes/macrophages and CD4+ and CD8+ cells markedly increased by day 5 and increased thereafter until day 10. The levels of mRNAs for MCP-1, MCP-3, and lymphotactin increased on day 5 and returned to their normal levels by day 7. The level of TCA3 mRNA increased on day 3, and that of MIP-1alpha mRNA increased on day 7, but both returned to their normal levels within 2 days. No increase in the mRNAs of MIP-1beta or RANTES was observed until day 10. These results indicate that the expression pattern of the chemokine mRNAs in glomeruli resembles that in renal cortex, but is more transient and sequential.