Abstract |
Liver microsomes of the rat contain a group of hydroxylating enzymes which are coupled to a greater or lesser degree to the electron flow system. In our studies, enzymes believed to be directly associated with the electron flow chain of NADPH, ferricyanide reduction, cytochrome c, cytochrome P-450 and substrate hydroxylation have been observed in livers obtained from normal, tumor-bearing and whole body irradiated rats as well as in Morris hepatoma 7777 and dimethyl-amino- biphenyl induced breast tumors.A significant difference appeared to exist in the activity of NADPH oxidase, NADP- ferricyanide reductase and benzopyrene hydroxylase when normal liver was compared with the liver obtained from a breast-tumor-bearing animal. Both cytochrome P-450 and cytochrome b(5) were decreased in the tumor-bearing animal.Tissue distribution of benzopyrene hydroxylase in normal, lactating and tumor-bearing Wistar rats has been studied.With the exception of NADPH oxidase, the activities of NADP- cytochrome c reductase, NADPH-ferricyanide reductase, benzopyrene hydroxylase and P-450 were markedly different in liver from Morris hepatoma 7777-bearing Buffalo rat when this was compared with homologous tissue obtained from normal Buffalo rat.Whole-body irradiated animals showed increased P-450 and NADPH oxidase activity in liver as a function of irradiation and there further appeared to be a correlation with decreased ferricyanide reductase activity.
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Authors | H D Brown, S K Chattopadhyay, S N Pennington, J S Spratt, H P Morris |
Journal | British journal of cancer
(Br J Cancer)
Vol. 25
Issue 1
Pg. 135-41
(Mar 1971)
ISSN: 0007-0920 [Print] England |
PMID | 4397226
(Publication Type: Journal Article)
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Chemical References |
- Benzopyrenes
- Biphenyl Compounds
- Cytochromes
- Ferricyanides
- NADP
- Mixed Function Oxygenases
- Oxidoreductases
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Topics |
- Animals
- Benzopyrenes
- Biphenyl Compounds
- Carcinoma, Hepatocellular
(enzymology)
- Colon
(enzymology)
- Cytochromes
(metabolism)
- Electron Transport
- Female
- Ferricyanides
(metabolism)
- Kidney
(enzymology)
- Lactation
- Liver Neoplasms
(enzymology)
- Lung
(enzymology)
- Male
- Mammary Neoplasms, Experimental
(chemically induced, enzymology)
- Microsomes, Liver
(enzymology, radiation effects)
- Mixed Function Oxygenases
(metabolism)
- NADP
(metabolism)
- Neoplasms, Experimental
- Oxidoreductases
(metabolism)
- Pregnancy
- Radiation Effects
- Rats
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