2001 年 14 巻 1 号 p. 51
Polycystic lesions of kidney and liver were found in Crj:CD(SD) rats of 9 males and 6 females ranging in age from 5 to 57 weeks and were histopathologically or immunohistochemically investigated. Renal cysts were observed in the outer medulla at the beginning and confirmed to be dilatations of the collecting ducts by Dolichos biflorus agglutinin lectin histochemistry. At an advanced stage, the cysts expanded toward the cortex owing to dilatation of the collecting ducts and distal tubules, inflammatory cell infiltration, and fibrosis surrounding the cysts were observed additionally. The TUNEL assay revealed apoptotic cell death in the tubular epithelium of the cysts. Electron microscopy represented slightly thickened and laminated basement membranes of the cysts.The liver lesion at the beginning revealed slight dilatation of bile ducts and lymphatic ducts in Glisson's sheath. At the advanced stage, dilatation of bile ducts spread over the liver, proliferation of bile ducts, desquamation of the biliary epithelium, and fibrosis surroundings the bile ducts were observed in addition to the cystic lesions. The histological features of the cystic lesions were similar to those of human autosomal recessive polycystic kidney disease (PKD). None of the rat PKD models presented concurrently the biliary cysts. Therefore, these rats may be a potential model for human PKD and be useful for studying the correlation of the pathogenesis between the renal cysts and the biliary cyst.
