Enzymes from several metabolic pathways were studied quantitatively in homogenates and in homogeneous areas of frozen‐dried cryostat sections of an experimental, mouse ependymoblastoma, mouse mammary carcinoma, and mouse melanoma, growing as transplants in mouse brain. Micro analyses were performed in fiveto sixfold replicates on portions of tumour with a dry weight of 0·03‐0·2 μg. A close resemblance of the enzyme spectrum of the ependymoblastoma to that of immature brain was noted. Hexokinase and malate dehydrogenase were lower and lactate, glucose‐6‐phosphate, and NADP+‐linked isocitrate dehydrogenases, and β‐glucuronidase higher in the ependymoblastoma than in whole, adult mouse brain. Mouse mammary carcinoma had a higher level of hexokinase and lower levels of lactate and glucose‐6‐phosphate dehydrogenases and β‐glucuronidase than ependymoblastoma. The concentration of malate dehydrogenase was lower and that of lactate, glucosed‐6‐phosphate, and NADP+‐linked isocitric dehydrogenases was higher in the melanoma than in the ependymoblastoma. β‐Glucuronidase levels were similar in these two neoplasms. It is suggested that the relatively high levels of several NADP+‐linked enzymes in the ependymoblastoma may be related to increased capacity for lipid synthesis.
|Number of pages||10|
|Journal||Journal of Neurochemistry|
|State||Published - Nov 1966|