PDGF Receptor-α Deficiency in Glomerular Mesangial Cells of Tenascin-C Knockout Mice

Abstract

Tenascin-C (TNC) knockout (TNKO) mice showed reduced proliferation of mesangial cells and abnormal restoration after habu-snake venom (HSV)-induced glomerulonephritis. In this study, we examined the relationship of TNC and platelet-derived growth factor receptor (PDGFR) in glomerular mesangial cells. TNC and PDGFR-α and -β transcriptions were up-regulated in wild type (WT) mice after HSV injection, but in TNKO mice PDGFR-α transcription was not up-regulated. Immunohistochemistry showed that PDGFR-α was found in mesangial areas of colocalized α-smooth muscle actin, but in TNKO mice it was not detectable. In vitro studies showed that the expressions of PDGFR-α and -β mRNA and protein in cultured glomerular mesangial cells (GMC) of TNKO mice were lower than those in WT GMC. These results suggest that failures of both TNC and PDGFR-α are a candidate for abnormal restoration of TNKO mice.