Glomerular ultrastructural change and vascular endothelial growth factor-A expression in diabetic cats.

Abstract

OBJECTIVES: To evaluate the glomerular ultrastructural changes associated with diabetic nephropathy and quantify glomerular vascular endothelial growth factor-A expression in cats with diabetes mellitus compared to controls. MATERIALS AND METHODS: Transmission electron microscopy was performed to evaluate glomerular ultrastructural changes, including glomerular endothelial cell fenestration density and width, glomerular basement membrane width, podocyte foot process width, and podocyte slit width and density in four diabetic and five control cats. Glomerular vascular endothelial growth factor-A expression was quantified using immunohistochemistry in eight diabetic and five control cats. RESULTS: Glomerular ultrastructural change consistent with diabetic nephropathy, including loss of glomerular endothelial cell fenestrations and thickened glomerular basement membrane, was present in diabetic cats. Furthermore, diabetic cats had increased glomerular vascular endothelial growth factor-A expression. CLINICAL SIGNIFICANCE: This study demonstrates that diabetic nephropathy may develop in diabetic cats, which although representing early subclinical disease, may contribute to decreased glomerular filtering capacity and proteinuria and therefore requires clinical monitoring.