In the present study, we examined the effects of IL-10 after 24 h in a model of acute glomerulonephritis (GN). One hour after the anti-Thy I antibody administration, a single i.v. dose of IL-10 was administered to rats. Normal rats, control nephritic rats and nephritic rats treated with IL-10, were sacrificed 24 h after administration of antibody. Samples of urine, blood and organs were subsequently collected. The effects of IL-10 were studied by quantification of various inflammatory parameters at the protein level after immunohistochemical staining and at the mRNA level by a quantitative real time PCR technique. Nitric oxide and protein content were determined in serum and in 24 h-excreted urine, respectively. The inflammatory parameters were reduced in the IL-10-treated group: in increment in glomerular CD14, ICAM-1 and MMP-13 staining induced by anti-Thy 1 injection was significantly attenuated by IL-10. In contrast, mRNA levels for CD14, IL-1 beta, TNF-alpha and MCP-1 were not different between IL-10-treated and control GN groups. In conclusion, a single i.v. dose of IL-10 suppresses the expression of several inflammatory parameters, 24 h after inducing of acute GN but at this time point mRNA levels of all parameters examined were not affected. Although its therapeutic efficacy needs further evaluation, anti-inflammatory effects of this short-lived cytokine can be found one day after its administration.