抄録
To the 5th right mammary gland of Sprague-Dawley female rats, ca 1mg of DMBA was directly administered by means of a dusting of its pure powder over the mammary fatty pad. At the site of administration, a nodule of adenocarcinoma was induced more than 7 weeks after the local application with high incidence. It was enhanced more in the adults than the youngs. Histochemically, atypisms of ALP and LDH activities were observed on the apparent malignant tissues induced by DMBA-dusting. Biochemical observations on the activities of LDH and MDH and on the pattern of LDH isoenzymes were done for the induced nodules with DMBA-dusting over females aged 8-26 weeks, which were harvested 5-18 weeks after the local application. The quotients of LDH/MDH in the same sample elevated on the malignant tissues prominently owing to higher LDH activity, and the elevation was moderate on the earlier-harvested, granulomatous tissues. But, the shift toward predominance of the M type of LDH was detected distinctly in the earlier granulomatous samples harvested 5 weeks after the local application.
