Tumor cells, Erlich-Ascites

Pyrazinamide is one of the most powerful drugs available for the inhibition of urate excretion in man, consistently providing a 80-90% reduction in the renal clearance of uric acid (1401, 1403). 2-Morpholinocarbonylpyrazine and its 6-methoxy derivative are claimed to have antidiabetic activity (948, 949, 1351, 1387, 1404), and some 2-(p-ureidosulfonylphenethylcarbamoyl)pyrazines have been shown to have hypoglycemic activity in mice (1405). The effect of 2-amino-3-hydroxy-carbamoylpyrazine on DNA synthesis by Erlich ascites tumor cells in vitro has been investigated (1406) as well as the inhibition by 2-amino-3-hydroxycarbamoylpyrazine on L-histidine carboxylyase (1407) many 2-hydroxyimidazo[4,5-6]pyrazines (prepared from 2-amino-3-hydrazinocarbonylpyrazines with nitrous acid) are potent hypotensive agents in animals (880,891,963,1181). 

Calcium chromate has been shown to induce cytoplasmic petite mutations in mitochondria of Saccharomyces cerevisiae K Calcium chromate also dramatically depressed the content of the mitochondrial gene products cytochrome aa3 and cytochrome b, in whole yeast cells. Chromate ( 8 nM) was readily taken up by rat thymocytes and after 30 min 9% of the Cr was found in the mitochondria although 62% was found in the nuclei . Isolated rat thymus mitochondria and nuclei readily took up CrOj . After one hour incubation of Erlich ascites tumor cells with CrOj (380 /nuclear fraction and 12% was in the mitochondrial-microsomal fraction. Levels of chromium in rat liver mitochondria reached a plateau six hours after i.v. injection of chromate (0.02 mg/kg) and remained at that level through 5 days. Liver nuclear chromium levels in the same animals, although similar to mitochondrial levels at 6 h, reached a maximum at 12 h and steadily decreased after that time. Therefore the nuclear chromium levels were lower than the mitochondrial chromium levels at later times (24-120 h) after injection. The subcellular distribution of chromium in the liver of rats injected i.v. with chromate (0.56 mg/kg) was also found to be time dependent in another study. The distribution of chromium in rat liver mitochondria increased from 5% at 15 min to 21% at 72 h and also increased in the nuclear fraction from 22% at 15 min to 52% at 72 h. Incubation of isolated rat liver mitochondria with chromate (0.3-16.6 electron transport chain of the mitochondrial iner membrane. 

Erlich ascites tumor cells by bioflavonoids. Biochemistry... 

Grazianl, Y. and Chayoth, R. (1979). Regulation of cyclic AMP level and synthesis of DNA, RNA and protein by quercetin In Erlich ascites tumor cells. Blochem. Pharmacol. 28, 397-403. 

Podhajcer, O.L., Friedlander, M. and Graziani,Y. (1980). Effect of liposome-encapsulated quercetin on DNA synthesis, lactate production, and cyclic adenosine 3 5 -monophosphate level in Erlich ascites tumor cells. Cancer Res. 40, 1344-1350. 

Reddy GV, Shahani KM and Benerjee MR (1973) Inhibitory effect of yogurt on Erlich ascites tumor cell proliferation. J Natl Cancer Inst 50 815-817 Reddy MS, Reinbold GW and Williams FD (1973) Inhibition of propionibacteria by antibiotic and antimicrobial agents. J Milk Food Technol 36 564-569 Reeves RE, Menzies RA and Hsu DS (1968) The pyruvate-phosphate dikinase reaction. J Biol Chem 243 5486-5491... 

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