Acid hydrolase and cytochrome oxidase activities in nitrosourea induced tumors of the nervous system.

Nitrosourea induced tumors of the nervous system in rats have proven useful for biochemical studies combined with morphological approaches. The pattern of enzyme activities for acid hydrolases and cytochrome oxidase resemble those previously observed in spontaneous nervous system tumors of man. The activities of 4 acid hydrolases were generally high in the gliomas. This could not be attributed solely to zones of regression or necrosis but was a general characteristic of the neoplasms. The activities were predominantly particulate and most likely lysosomal in localization. In schwannomas a similar increase in hydrolases was found in comparison with normal neural tissues but aryl-sulfatase was not increased. Cytochrome oxidase activities were markedly reduced in all tumors studied. The proportionate reduction with respect to normal brain was comparable to that noted in man. No differences were found with respect to fairly well differentiated gliomas.