Enzyme-histochemical Studies on Histogenesis of Diethylstibestrolinduced Kindey Tumor of Hamster with Special Reference to Alkaline Phosphatase Activity

Histochemical investigation were made on various enzymes of DES-induced kidney tumors of the Syrian hamster. The tumors were classified morphologically into two types with epithelial and non-epithelial feature. In spite of varied histological pictures they showed similar enzymatic activities and this result suggested that both types had a common origin. Furthermore, through a consideration of alkaline phosphatase activity, the site of origin was identified as the proximal convoluted tubules. This idea was further supported by the fact, in this portion of nephron, there existed anaplastic hyperplastic cell nests whose enzymes were of same pattern as those of the tumors. The dark cell type appeared tobe a prototype of all other forms. Even a spindle cell type could not be regarded as originating from fibloblast. Also interesting was the observation that ever since thire incipient stage the neoplastic cells had carried all the enzymatic characteristics of the tumor.