Nephropathy induced by renal microembolism: a characterization of biochemical and histopathological changes in rats

The aim of this study was to investigate some biochemical parameters of renal function and the vascular, glomerular, tubular, and interstitial manifestations in the progression of nephropathy induced by renal microembolism. Renal microembolism was induced by the arterial injection of polymethacrylate microspheres in the remnant kidney of nephrectomized rats. Animals 110-120 days old were randomly divided into three groups: the control group (C; normal), the nephrectomized group (S; nephrectomized that did not undergo renal microembolism), and the model group (M, nephrectomized animals that underwent renal arterial microembolism). The animals were evaluated 30, 60, and 90 days after the induction of a renal microembolism. Blood and urine samples were collected to determine serum creatinine (Cr) and urea (Ur) concentrations and urine total protein (Pt) concentrations. The kidneys were weighed and processed for histopathological analysis using hematoxylin and eosin (HE), periodic acid-Schiff (PAS), Mallory-Azan, and Picro-Sirius staining. The samples were also subjected to immunohistochemistry with a proliferating cell nuclear antigen (PCNA) and a vascular endothelial growth factor receptor (VEGFR). The data demonstrated evidence of the occurrence of vascular, glomerular, tubular, and interstitial abnormalities in the renal tissue, and changes in the biochemical parameters of renal function (serum Cr and Ur and of 24-h urine Pt) in this experimental model of nephropathy induced by renal microembolism, which may indicate the development of chronic kidney disease (CKD). Additionally, the findings indicate that this is a good reproducibility model that may be useful for studying the pathogenesis of CKD that is caused by atheroembolism and possible treatment alternatives.