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Sato A, Nakajima T. Dietary carbohydrate‐ and ethanol‐induced alteration of the metabolism and toxicity of chemical substances. Nutr Cancer 2009. [DOI: 10.1080/01635588509513815] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Luotamo M, Elovaara E, Raunio H, Pelkonen O, Riihimäki V, Vainio H. Distribution and effects on cytochrome P450 system of two hexachlorobiphenyl isomers in the rat. Arch Toxicol 1991; 65:661-5. [PMID: 1747066 DOI: 10.1007/bf02098033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Tissue distribution and effects induced by 2,2',4,4',5,5'-hexachlorobiphenyl (245-HCB) on cytocrome P450 isozymes were compared with those of 2,2',3,3',6,6'-hexacholorobiphenyl (236-HCB). Male Wistar rats were given a single intragastric dose (23 mg/kg body wt) of either isomer, and killed after 72 h. At termination the tissue concentrations of 245-HCB were considerably higher than those of 236-HCB, suggesting a more effective metabolism of the latter. The binding affinity of 236-HCB to cytochrome P450 was higher and the magnitude of binding greater than of 245-HCB. 245-HCB-treatment elevated the hepatic concentration of cytochrome P450 and also the activities of 7-pentoxyresorufin O-depentylase (50-fold), aniline p-hydroxylase (2-fold) and 7-ethoxycoumarin O-deethylase (2-fold), a response typical of phenobarbital-type inducers. In the Western immunoblot of liver microsomes from 245-HCB treated rats, an increased amount of P450IIB 1/2 was detected by a monoclonal antibody 2-66-3, which specifically detects phenobarbital inducible isoenzymes. The minimum molecular mass of the P450 isozyme induced was 52 kDa. After 236-HCB administration, a weak inducing effect was observed.
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Affiliation(s)
- M Luotamo
- Institute of Occupational Health, Department of Industrial Hygiene and Toxicology, Helsinki, Finland
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Sato A, Nakajima T. Enhanced metabolism of volatile hydrocarbons in rat liver following food deprivation, restricted carbohydrate intake, and administration of ethanol, phenobarbital, polychlorinated biphenyl and 3-methylcholanthrene: a comparative study. Xenobiotica 1985; 15:67-75. [PMID: 3920836 DOI: 10.3109/00498258509045336] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The effects of food deprivation, carbohydrate restriction and ethanol consumption on the metabolism of eight volatile hydrocarbons (benzene, toluene, styrene, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene and trichloroethylene) in rats were compared with the effects of enzyme induction by phenobarbital (PB), polychlorinated biphenyl (PCB) and 3-methylcholanthrene (MC) on the metabolism of these compounds. Although causing a marked increase both in microsomal protein and cytochrome p-450 contents, PB (80 mg/kg per day for three days) and PCB (a single dose of 500 mg/kg) induced only a limited range of enzyme activity: PB increased the metabolism of toluene, styrene, chloroform, carbon tetrachloride and trichloroethylene, and PCB only increased those of toluene, styrene and trichloroethylene. MC (20 mg/kg per day for three days) had no effect on the metabolism of any of the hydrocarbons studied. In contrast, food deprivation, carbohydrate restriction and three-week ingestion of ethanol (2.0 g/day), each enhanced the metabolism of all the hydrocarbons with little or no increase in microsomal protein and cytochrome P-450 contents. PB, PCB and MC treatments enhanced the activity of enzymes involved in conjugation reactions, UDP-glucuronyltransferase and glutathione S-transferase, whereas the dietary manipulation and ethanol consumption produced no significant effect on these enzymes. It is concluded that ethanol consumption. lowered carbohydrate intake and food deprivation affect the metabolism and toxicity of volatile hydrocarbons differently from PB, PCB or MC.
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Ahotupa M, Hietanen E, Mäntylä E, Vainio H. Effects of polchlorinated paraffins on hepatic, renal and intestinal biotransformation rates in comparison to the effects of polychlorinated biphenyls and naphthalenes. J Appl Toxicol 1982. [DOI: 10.1002/jat.2550020111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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McCormack KM, Roth RA, Wallace KB, Ross LM, Hook JB. Nonrespiratory metabolic function and morphology of lung following exposure to polybrominated biphenyls in rats. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1982; 9:27-39. [PMID: 6278155 DOI: 10.1080/15287398209530139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Exposure to polybrominated biphenyls (PBBs) resulted in increased activity of microsomal arylhydrocarbon hydroxylase and ethoxyresorufin-O-deethylase in rat lung. Clearance of 5-hydroxytryptamine (5-HT) and angiotensin 1 by perfused lungs was decreased by PBBs. However, PBBs had no effect on the activity of epoxide hydrolase, monoamine oxidase, or angiotensin-converting enzyme in lung. The only histopathologic change detected in lungs from PBB-treated rats was an increase in alveolar type II cell lamellar bodies. Selective accumulation of certain PBB congeners by lung was not observed in this investigation.
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Heinonen T, Vainio H, Nickels J. Effects of vinyltoluene alone and after pretreatment with polychlorinated biphenyls on hepatocellular morphology and enzyme activities in liver and kidneys in rats. Toxicology 1981; 22:297-310. [PMID: 6805099 DOI: 10.1016/0300-483x(81)90024-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Narbonne JF. Time course of induction of microsomal enzymes following dietary administration of a polychlorinated biphenyl (Phenoclor DP6). Toxicol Appl Pharmacol 1980; 56:1-7. [PMID: 6777906 DOI: 10.1016/0041-008x(80)90125-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Ghazarian J, Martinex J, Gallardo A, Kulkoski J, Peterson B. Induction of renal cytochrome P-450 by the polychlorinated biphenyl Aroclor-1254. Mitochondrial distribution and correlation with the calcium-regulating mixed function oxidases 1 alpha- and 24R-hydroxylases of 25-hydroxyvitamin D3. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)70643-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Lake BG, Collins MA, Harris RA, Gangolli SD. The induction of hepatic and extrahepatic xenobiotic metabolism in the rat and ferret by a polychlorinated biphenyl mixture (Aroclor 1254). Xenobiotica 1979; 9:723-31. [PMID: 119357 DOI: 10.3109/00498257909042340] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
1. The effect of a single i.p. dose (500 mg/kg) of a polychlorinated biphenyl mixture (Aroclor 1254) on hepatic and extrahepatic xenobiotic metabolism in male rat, and male and female ferret, was studied. 2. Aroclor 1254 treatment induced hepatic microsomal N-demethylase activities, and cytochrome P-450 and protein content in both rat and ferret. Liver size and aniline 4-hydroxylase were also increased in rat, but not ferret. The polychlorinated biphenyl mixture appeared to be a mixed-type inducer of hepatic xenobiotic metabolism in both species. 3. Aroclor 1254 treatment produced large increases in activities of benzo(a)pyrene hydroxylase and 7-ethoxycoumarin O-deethylase in whole homogenates of the liver, small intestinal mucosa, kidneys and lungs of both species. Maximal stimulation of xenobiotic metabolism occurred in the kidney of both the rat and ferret. In contrast, UDP-glucuronyltransferase activity was only stimulated in liver, intestine and kidney of the rat and in liver and intestine of the ferret. 4. These results suggest a general species similarity in the response to the polychlorinated biphenyl mixture between the rat and ferret.
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Shimada T, Sato R. Inhibition of mono-oxygenase activities by 1,1,1-trichloropropene 2,3-oxide, an inhibitor of epoxide hydrase, in rat liver microsomes. Biochem Pharmacol 1979; 28:1777-81. [PMID: 475837 DOI: 10.1016/0006-2952(79)90540-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Berry DL, Slaga TJ, DiGiovanni J, Juchau MR. Studies with chlorinated dibenzo-p-dioxins, polybrominated biphenyls, and polychlorinated biphenyls in a two-stage system of mouse skin tumorigenesis: potent anticarcinogenic effects. Ann N Y Acad Sci 1979; 320:405-14. [PMID: 222192 DOI: 10.1111/j.1749-6632.1979.tb56621.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Schmoldt A, Benthe HF, Haberland G. Impaired biliary excretion of digitoxin and its metabolites after treatment with polychlorinated biphenyls. Toxicol Appl Pharmacol 1979; 47:483-91. [PMID: 108813 DOI: 10.1016/0041-008x(79)90519-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Ryan D, Thomas P, Korzeniowski D, Levin W. Separation and characterization of highly purified forms of liver microsomal cytochrome P-450 from rats treated with polychlorinated biphenyls, phenobarbital, and 3-methylcholanthrene. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(17)34211-4] [Citation(s) in RCA: 470] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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McCormack KM, Melrose P, Rickert DE, Dent JG, Gibson JE, Hook JB. Concomitant dietary exposure to polychlorinated biphenyls and polybrominated biphenyls: tissue distribution and arylhydrocarbon hydroxylase activity in lactating rats. Toxicol Appl Pharmacol 1979; 47:95-104. [PMID: 218325 DOI: 10.1016/0041-008x(79)90076-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Burke MD, Orrenius S. Isolation and comparison of endoplasmic reticulum membranes and their mixed function oxidase activities from mammalian extrahepatic tissues. Pharmacol Ther 1979; 7:549-99. [PMID: 392562 DOI: 10.1016/0163-7258(79)90042-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Carpanini FM, Butterworth KR, Gaunt IF, Kiss IS, Grasso P, Gangolli SD. Long-term toxicity studies on Chocolate Brown HT in rats. Toxicology 1978; 11:303-7. [PMID: 734686 DOI: 10.1016/s0300-483x(78)91839-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Groups of 48 males and 48 female rats were given diets containing 0 (control), 500, 2000 or 10,000 ppm Chocolate Brown HT for 2 years. These treatments had no adverse effect on mortality, body-weight gain, food or water consumption, haematology, renal function, serum constituents, organ weight or histopathology. From the incidence of tumours observed in the control and test animals it is concluded that Chocolate Brown HT did not exert any carcinogenic effect and that the no-untoward-effect level was 10,000 ppm.
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Parkki MG, Marniemi J, Vainio H. Long-term effects of single and combined doses of DDT and PCB on drug-metabolizing enzymes in rat liver. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1977; 3:903-11. [PMID: 413932 DOI: 10.1080/15287397709529624] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Two common environmental pollutants, DDT and a polychlorinated biphenyl (PCB) mixture (Clophen A-50), were administered ip to rats in discrete single doses (160 and 100 mg/kg, respectively) and in combination. All the enzyme activities studied were enhanced by DDT and PCB. the overall drug hydroxylation reactions, and their components, achieved maximal induction in 1 wk. The cytochrome P-450 content of microsomes was increased nearly fourfold and NADPH-cytochrome c reductase activity was enhanced twofold by both compounds. p-Nitroanisole O-demethylase was increased sevenfold by PCB and fourfold by DDT, aryl hydrocarbon hydroxylase threefold by PCB and 1.7-fold by DDT. After 2 wk the activities began to decline. Distinct increases in enzyme activities were still detectable 1 month after a single dose. Epoxide hydratase and UDPglucuronosyltransferase activities were also enhanced in 1 wk (epoxide hydratase 2.5-fold by both compounds, UDPglucuronosyltransferase tenfold by PCB in trypsin-activated microsomes but only threefold by DDT). The disappearance of induction in epoxide hydratase was slower than in the monooxygenases, and UDPglucuronosyltransferase still showed a trend toward increased activity 4 wk after the administration. The DDT-enhanced UDPglucuronosyltransferase activity slightly returned toward the control level. Glutathione S-transferase differed from the microsomal enzymes in that it was already elevated 1 day after the administration of both DDT and PCB. Its activity was only doubled, but the increased activity remained at almost the same level through the whole 1 month period.
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Marniemi J, Nokkala M, Vainio H, Hartiala KJ. Stimulation of hepatic drug hydroxylation and conjugation by a cutaneously applied PCB-mixture (clophen A 50). Chem Biol Interact 1977; 18:247-51. [PMID: 408019 DOI: 10.1016/0009-2797(77)90011-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Arcos JC, Davies DL, Brown CE, Argus MF. Repressible and inducible enzymic forms of dimethylnitrosamine-demethylase. ZEITSCHRIFT FUR KREBSFORSCHUNG UND KLINISCHE ONKOLOGIE. CANCER RESEARCH AND CLINICAL ONCOLOGY 1977; 89:181-99. [PMID: 143144 DOI: 10.1007/bf00308517] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Wolff T, Hesse S. Species differences of mixed-function oxidase induction between rabbits and rats after pretreatment with polychlorinated biphenyls (PCBs). Biochem Pharmacol 1977; 26:783-7. [PMID: 405014 DOI: 10.1016/0006-2952(77)90225-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Schmoldt A, Herzberg W, Benthe HF. On the inhibition of microsomal drug metabolism by polychlorinated biphenyls (PCB) and related phenolic compounds. Chem Biol Interact 1977; 16:191-200. [PMID: 403020 DOI: 10.1016/0009-2797(77)90128-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The in vitro metabolism of p-nitroanisole, aminopyrine, and aniline by rat liver microsomal monoxygenases were studied in the presence of different polychlorinated biphenyl (PCB) mixtures and some related hydroxybiphenyls. The tested PCB mixtures contained preferably dichloro- (di-CB), tetrachloro- (tetra-CB), or hexachlorobiphenyls (hexa-CB). All PCB were competitive inhibitors of only aminopyrine demethylation by normal microsomes (Ki 22-39 micron). In microsomes of PCB-pretreated rats the aminopyrine demethylation was inhibited noncompetitively by di-CB and hexa-CB whereas tetra-CB remained a competitive inhibitor (Ki 12 micron). Moreover, after PCB pretreatment all PCB were competitive inhibitors of p-nitroanisole demethylation. 2-OH-biphenyl and 4-OH-biphenyl caused competitive inhibition of aminopyrine demethylation and aniline hydroxylation but failed to inhibit p-nitroanisole metabolism by normal microsomes. Chlorinated 4-hydroxybiphenyls inhibited competitively the metabolism of both type I and type II substrates. However, after PCB pretreatment all phenolic compounds caused uncompetitive inhibition of aniline hydroxylation.
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Stonard MD, Greig JB. Different patterns of hepatic microsomal enzyme activity produced by administration of pure hexachlorobiphenyl isomers and hexachlorobenzene. Chem Biol Interact 1976; 15:365-79. [PMID: 827338 DOI: 10.1016/0009-2797(76)90141-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Three hexachlorobiphenyl isomers, 2,2',4,4',5,5'-hexachlorobiphenyl (I), 2,2',3,3',4,4'-hexachlorobiphenyl (II) and 2,2',3,4,4',5'-hexachlorobiphenyl (III), have been administered to rats and the effects of these three compounds upon hepatic microsomal drug metabolism and upon hepatic porphyrins have been studied. Comparisons have been made with hexachlorobenzen and a commercial polychlorinated biphenyl mixture, Aroclor 1254. From measurements of activities of microsomal drug oxidations in vitro, the durations of pharmacological actions of certain drugs in vivo and spectral shifts associated with cytochrome P-450 it is shown that the three pure hexachlorobiphenyl isomers initially produce changes in hepatic microsomal activity which resemble those seen after treatment with phenobarbitone (PB). In contrast, following chronic feeding of the isomers, compounds II and III but not I produce a pattern of hepatic microsomal enzyme activity which shows some characteristics of the 3-methylcholanthene (3-MC) and some characteristics of the phenobarbitone classes of inducer. Also, compounds II and III, but not I, cause accumulation in the liver of porphyrins containing either seven or eight carboxyl groups. These two responses are similar to those observed following hexachlorobenzene treatment and suggest that a relationship may exist between the mixed pattern of enzyme induction and the onset of hepatic porphyrin accumulation.
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Cappon ID, Young ET, Nicholls DM. An environmental chemical, polychlorinated biphenyl, increases the protein synthesizing activity of liver and kidney pH 5 supernatant fractions. Chem Biol Interact 1976; 14:127-34. [PMID: 821622 DOI: 10.1016/0009-2797(76)90030-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Homogenates of liver and of kidney cortex were obtained from control rats and from rats treated with the polychlorinated biphenyls (PCBs), Aroclor 1254, and were separated into ribosomes and into the postmicrosomal supernatant fraction. The latter fraction from liver and kidney was used to prepare the pH 5 supernatant fraction, containing elongation factors 1 and 2 (EF 1 and EF 2) for protein biosynthesis. These fractions were incubated with KCl-washed ribosomes obtained from control rat liver. The incorporation of [14C] phenylalanyl-tRNA into peptide was increased with the liver and kidney preparations derived from the treated rats. The elongation factor 1-dependent binding of [14C] phenylalanyl-tRNA to ribosomes was also markedly increased both with the liver and kidney preparations obtained from the rats that had received PCBs.
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Abstract
Multiple factors contribute to the development of neoplasia. Sometimes a single agency can bring about a tumour if it has many different effects, but at other times a tumour arises more insidiously due to a succession of events [240,241] which by themselves may be innocent. Alterations in the genome of the cell are at the fore-front of our interest because they can be brought about by most of the carcinogenic agents we know. The cell can repair some such alterations but both forward and destructive mutations do appear. The roles of cell proliferation, cell differentiation, the immune mechanism and carcinogen-activating enzymes are beginning to be understood. The effects of dose, route of administration, and of other agents given at the same time [242-245] must not be lost sight of. Other factors no doubt will be added as we begin to look at the structure and function of cell-surface membranes [246-248], at host susceptibility genetics [26, 249], and at the generation of carcinogens inside the body [250,251]. We are only beginning to understand carcinogenesis. In no single instance do we as yet know how a tumour comes about in full details of molecular biology. It is possible that fully rational treatment of cancer will not be possible until we have such an understanding. Once a tumour becomes independent of carcinogenic factors, it continues to develop in a bizarre fashion which makes its study and treatment by all means other than surgery difficult.
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Laitinen M, Lang M, Hietanen E, Vainio H. Enhancement of hepatic drug biotransformation rate by polychlorinated biphenyls in rats fed cholesterol-rich diet. Toxicology 1975; 5:79-88. [PMID: 810923 DOI: 10.1016/0300-483x(75)90072-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A combined effect of cholesterol and polychlorinated biphenyls (PCBs) on the microsomal drug hydroxylation and glucuronidation in the liver of the rat was studied. PCBs, Clophen A-50 and A-60, having an average chlorination degree of 50 and 60% affect the structure of microsomal membranes. It was found that Clophen A-60 increased the binding of trypsin- and digitonin-sensitive proteins to the membranes. Also it was found that PCBs enhanced the phsopholipid content of microsomes. PCBs increased the activity of hepatic NADPH cytochrome c reductase about 1.5-fold. Aryl hydrocarbon hydroxylase activity doubled with Clophen A-50 and quadrupled with Clophen A-60. Hepatic UDPglucuronosyltransferase activity was doubled with both PCBs. The enhancement in hepatic aryl hydrocarbon hydroxylase and in UDPglucuronosyltransferase was found to be lower in the presence of high cholesterol level in the diet when compared to earlier results. This is supposed to be due to the membraneous effects of cholesterol.
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