microRNAs profiles of contrast-induced acute kidney injury rats

Contrast-induced acute kidney injury (CI-AKI) is typically defined by an increase in serum creatinine (SCr) after intravascular administration of contrast medium. Since creatinine is an unreliable indicator for acute changes in kidney function, an early biomarkers for CI-AKI diagnosis is important for initiating therapy.We assessed the hypothesis that circulating microRNAs (miRNAs) could be served as potential biomarkers to early detect CI-AKI.The rat model of acute kidney injury was developed as we previously described. We first detect miRNA profile of plasma and kidney tissue using Agilent microarray platform. 3 miRNA species with > 1.5-fold increase in plasma samples of CI-AKI rats, including miRNA-30a, miRNA-30e and miRNA-188, were selected as candidate miRNAs of potential biomarkers. 24 rats were randomly divided into 2 groups (CI-AKI group and control group), each with 4 subgroups (n=3). Peripheral blood and kidney samples were harvest at 8h after contrast medium/normal saline administration. Total RNA sample from each rat in the same subgroup was combined together as pooled sample for further test. The Agilent microarray platform was adapted to profile the miRNA spectra.