[Polyamine oxidative deamination in hepatomas with varying growth rates].
Rates of oxidative deamination of polyamines were studied in rapidly growing hepatomas G-22 and G-27, in slowly growing hepatomas G-60, G-61, G-48, G-46 as well as in liver tissue of tumor-bearing animals and animals treated with nitrose piperidine. Diamine oxidase activity was not found in rapidly growing hepatomas. Treatment with pyridoxal-phosphate did not restore the diamine oxidase activity in hepatomas G-27, but distinctly increased the latter in the liver tissue of the tumor-bearing animals up to the level of the enzymatic activity found in liver tissue of the intact animals. On the contrary, high concentrations of pyridoxal-phosphate (above 0.02 mg) inhibited the diamine oxidase activity in liver tissue of the impaired and intact animals. The enzymatic activity was markedly decreased in slowly growing hepatomas G-60, G-61, G-48 and G-46 as compared with the activity in liver tissue of tumor-bearing animals. Oxidation of all the substrates used could be measured using hepatoma G-60, putrescine and spermidine - for hepatoma G-61, but only putrescine - for hepatoma G-48. No of the substrates used was deaminated by hepatoma G-46. Four-fold decrease in the diamine oxidase activity was observed during malignization of liver cells induced by nitrose piperidine. The diamine oxidase was mainly localized in the postmitochondrial fraction of hepatocytes.
D006631:Amine Oxidase (Copper-Containing) / Q000378:metabolism; D000818:Animals; D003641:Deamination; D004789:Enzyme Activation; D008099:Liver / Q000201:enzymology; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D009603:Nitroso Compounds; D010084:Oxidation-Reduction; D010880:Piperidines; D011073:Polyamines / Q000378:metabolism*; D051381:Rats; D013379:Substrate Specificity
D009603:Nitroso Compounds; D010880:Piperidines; D011073:Polyamines; D006631:Amine Oxidase (Copper-Containing)
Okislitel'noe dezaminirovanie poliaminov v gepatomakh s razlichnoĭ skorost'iu rosta.