Blood Catalase Research Articles

Serum xanthine oxidase: origin, regulation, and contribution to control of trypanosome parasitemia.

African trypanosomiasis is caused by Salivarian trypanosomes, tsetse fly-transmitted protozoa that inhabit the blood plasma, lymph and interstitial fluids, and, in the case of Trypanosoma brucei species, also the cerebrospinal fluid of mammal hosts. Trypanosomiasis in people and domestic animals manifests as recurring waves of parasites in the blood and is typically fatal. In contrast, trypanosomiasis in Cape buffaloes, which are naturally selected to resist the disease, is characterized by the development of only one or a few waves of parasitemia, after which the infection becomes cryptic, being maintained by the presence of 1-20 mammal-infective organisms/ml of blood. The control of the acute phase of parasitemia in Cape buffaloes correlates with a decline in blood catalase activity and the generation of trypanocidal H(2)O(2) in serum during the catabolism of endogenous purine by xanthine oxidase. Here we review features of this response, and of trypanosome metabolism, that facilitate H(2)O(2)-mediated killing of the parasites with minimal damage to the host. We also discuss the origin and regulation of serum xanthine oxidase and catalase, and show how recovery of serum catalase in infected Cape buffaloes precludes a role for H(2)O(2) in the long-term, stable suppression of trypanosome parasitemia.

Blood catalase and haematocrit values in a breeding colony of Dutch-belted rabbits

Rabbit seminal plasma catalase is much higher than in the semen of other mammals, and differences appear to be inherited. Because of the scarcity of information on rabbit blood catalase and haematocrit in Dutch-belted rabbits, an investigation of possible effects of gender, age and genetics on these variables was undertaken. There were 191 rabbits sampled at 2-3 months, 130 at 12 months and 61 at 18-24 months of age. There was no age effect on the haematocrit values and on blood catalase activity. At 12 months of age males had an average haematocrit value of 44% compared with 40% for females (P < 0.05). Corresponding average catalase values were 431 and 356 units/ml of blood (P < 0.05). Also catalase was measured in the semen and blood of 34 males, and males differed in both their blood and semen catalase activity (P < 0.05). The correlation between the two traits was r = 0.44. Heritability (h2) estimates, based on 231 rabbits were 0.40 for blood catalase activity, and 0.26 for haematocrit. The genetic correlation between the two variables was 0.83 (P < 0.05). These studies are consistent with the literature in that female rabbits have a slightly lower haematocrit value than males, and this is associated with a lower catalase activity. This appears to be the first report of a study that compares rabbit blood catalase in males and females of different ages. Preliminary evidence that differences may have a heritable basis is consistent with previous studies on rabbit semen catalase.

A New Type of Inherited Catalase Deficiencies: Its Characterization and Comparison to the Japanese and Swiss Type of Acatalasemia

ABSTRACTThirteen Hungarian families that exhibited inherited catalase deficiencies have been detected. Differences between the deficiencies reported from Hungary and the previously reported Swiss acatalasemia were characterized using biochemical analysis of the catalase proteins. Molecular biological methods were used to compare the previously reported types of catalase deficiencies in Japan and the Hungarian deficiencies. Three mutations (a GA insertion in exon 2, a G insertion in exon 2, and a T to G substitution in intron 7) are responsible for decreased catalase activity in 7 of the 13 Hungarian kindreds; the other 6 families have not yet been characterized. These are not the mutations observed in Japan. Changes in lipid and carbohydrate metabolism and the high incidence (12.7%) of diabetes mellitus in the Hungarian kindreds suggest that individuals with inherited catalase deficiency are at risk of atherosclerosis and diabetes mellitus. The Hungarian subjects were detected during screening of a large population for catalase activity; no overt disease state was associated with the deficiencies. We hypothesize that the increased risk of disease may be due to prolonged exposure to elevated levels of blood hydrogen peroxide due to the lack of normal removal of hydrogen peroxide by blood catalase.

A common functional C-T substitution polymorphism in the promoter region of the human catalase gene influences transcription factor binding, reporter gene transcription and is correlated to blood catalase levels

Oxidative stress is implicated in disease and aging. In order to obtain molecular genetic tools that can be used to determine the potential impact of oxidative stress we examined the human catalase gene promoter for possible variation. Genomic DNA isolated from 10 individuals was screened for polymorphisms in the 5′-flanking region by direct sequence analysis of PCR products (nt −307 to −46 from the transcription start site). A common C/T polymorphism −262 base pairs from the transcription start site was detected. Computer analysis indicated that the two variants bound different transcription factors. Indeed, gel retardation analysis revealed different protein binding patterns to the two variants. Expression studies with reporter constructs showed significantly higher transcriptional activity of the T variant in HepG2 and K562 cells (1.5-fold, p < .05 Wilcoxon test). Thus a higher expression in human liver and blood cells is possible. In order to test this hypothesis, catalase levels in red blood cells were determined in 29 donors. The corresponding genotype was determined with a restriction enzyme-based assay. It was found that catalase levels were significantly higher in donors carrying the T allele in comparison to donors homozygous for the C allele ( p < .03). In conclusion, we report here the first common (allele frequency in a Swedish population, 28%) genetic variant in a fundamental oxidative stress protection gene with a defined phenotype.

A Novel Catalase Mutation (a GA Insertion) Causes the Hungarian Type of Acatalasemia

ABSTRACTAcatalasemia, a deficiency of enzyme catalase, is an autosomal recessive syndrome with an incidence of 5:106 in Hungary. We have examined the first Hungarian acatalasemic family for the disease-causing mutation. All exons of the catalase gene were screened by PCR-SSCP, PCR-heteroduplex, and nucleotide sequence analysis. The heteroduplex formation detected in exon 2 was verified by nucleotide sequence analysis. We found a GA insertion at nucleotide position 138, increasing the GA repeat number from 4 to 5. This GA insertion caused a frameshift in the amino acid sequence from position 68 to 133 and generated a TGA terminating codon at amino acid position 134. This truncated protein lacks the essential amino acid (histidine 74) in the active center. This finding can explain the decreased blood catalase activity in the Hungarian acatalasemic family.

The modifying effect of β-carotene on gamma radiation-induced elevation of oxidative reactions and genotoxicity in male rats

The aim of the present work was to evaluate the modulatory role of β-carotene on the radiation-induced changes in certain biochemical and cytogenetic parameters. β-Carotene was given by gavage at a dose of 5 mg/kg body weight for 7 consecutive days before whole body gamma irradiation with 7 Gy (single dose). The levels of β-carotene in plasma, thiobarbituric acid-reactive substances (TBARS) in plasma and liver, the activities of superoxide dismutase (SOD) and catalase in blood and liver were the selected parameters. Furthermore, the frequency of micronuclei (MN) of polychromatic erythrocytes (PCEs), normochromatic erythrocytes (NCEs), the ratio of PCEs/NCEs and the mitotic index (MI) of bone marrow cells were also evaluated. The biochemical and cytogenetic determinations were carried out 1, 24, and 72 h after radiation exposure. The results obtained revealed that administration of β-carotene pre-irradiation significantly inhibited the decrease in plasma β-carotene, significantly reduced the levels of TBARS in plasma and liver. Significant protection of the radiation-induced changes in the activities of SOD and catalase was also recorded in the blood and liver of β-carotene-treated and -irradiated rats. β-Carotene resulted in significant inhibition in the frequency of radiation-induced MN, as well as in the ratio of PCEs/NCEs and the MI of bone marrow cells. These results suggest that β-carotene as a natural product with its antioxidant capacity and capability of quenching singlet oxygen, could play a modulatory role against the cellular damage affected by free radicals induced by whole body irradiation.

Infection-associated decline of cape buffalo blood catalase augments serum trypanocidal activity.

Clearance of trypanosomes from the blood of infected Cape buffalo was associated with the development of two responses: (i) complement-dependent and clone-specific lytic activity and (ii) complement-independent trypanocidal activity that was not restricted by trypanosome clone or species. This latter activity was mediated by H2O2 and required the presence of xanthine oxidase in serum but not the addition of purine substrates. Expression of the xanthine oxidase-dependent trypanocidal activity in Cape buffalo serum was coincident with, and required, a decline in its H2O2 catabolic activity. The H2O2 catabolic activity of Cape buffalo serum was due solely to catalase and declined by eightfold around the time that trypanosomes were cleared from the blood, accompanied by a fivefold drop in erythrocyte-associated catalase activity. The Cape buffalo did not develop subsequent parasitemic waves. Clearance of parasitemia in similarly infected cattle was also associated with development of trypanosome clone-specific lytic activity, but not with the acquisition of H2O2-dependent trypanocidal activity in serum, and the cattle supported recurring parasitemia. The lack of trypanocidal activity in pre- and postinfection cattle sera was due to their low content of xanthine oxidase and sustained catalase activity. These data strongly suggest that an infection-induced serum oxidative response, the efficacy of which is amplified by a decline in blood catalase, contributes to suppression of recurring parasitemia in Cape buffalo.

Changes in Liver Enzyme Activity in the TeleostSparus auratain Response to Cadmium Intoxication

Enzyme activity modulation by cadmium in the liver of the teleost fishSparus auratawas investigatedin vivofollowing 3 and 6 days of CdCl2administration (2.5 mg/kg body wt). The specific activities of the mitochondrial enzymes NAD-isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase were stimulated by approximately 20% after 3 days administration and were further increased (by about 40%) after 6 days treatment. In comparison with these enzymes, the activities of glutamate–oxaloacetate transaminase (GOT) and glutamate–pyruvate transaminase (GPT) in mitochondria were less stimulated after the two indicated intervals of treatment. Cadmium significantly reduced the activities of liver cytoplasmic GOT and GPT while a simultaneous increase occurred in the serum activities of these same enzymes. The activity of liver NADPH-cytochrome P450 reductase was stimulated by 25 and 40% after 3 and 6 days cadmium intoxication, respectively. Lastly, the antioxidant enzymes glutathione peroxidase and glutathione reductase in liver and catalase in both liver and blood were strongly reduced after 3 and 6 days cadmium administration. These data suggest that cadmium in fish hepatocytes alters cell membrane structure and concomitantly induces some perturbation in the integrity of the mitochondrial membrane.

Genetic heterogeneity of the 5′ uncoding region of the catalase gene in Hungarian acatalasemic and hypocatalasemic subjects

The 5′ uncoding region (165 bp), exon 1 (63 bp) and part of intron 1 (20 bp) of the catalase gene was amplified by PCR in acatalasemic (2), hypocatalasemic (19) patients and healthy individuals (10). The single strand conformational polymorphism of PCR products showed a highly polymorphic pattern. This polymorphism was supported by nucleotide sequence analyses yielding eight mutations. They are A to T, C to A and C to T at positions −21, −20, −18 of the 5′ flanking region, T to C at positions 4, 44, 49 of the non-coding region and C to T and C to A at positions 12, 27 of exon 1. Of these nucleotide substitutions, the fourth, fifth, seventh and eighth are novel mutations. The mutations 1, 3, 6, 8 were present at least at heterozygous level in all acatalasemics and hypocatalasemics. None of these mutations may be the causal mutation(s) of acatalasemia as each of these nucleotide substitutions were detected in healthy subjects with normal blood catalase activity.

Superoxide dismutase, catalase and glutathione peroxidase activities in human blood: influence of sex, age and cigarette smoking.

To obtain reference ranges for each of the main antioxidant enzymes (AOE) and analyze the influence of sex, age, and cigarette smoking on AOE activity in human blood. We investigated superoxide dismutase (SOD), catalase (CAT), and seleno-dependent glutathione peroxidase (GSH-Px) activities in the whole blood from 103 healthy subjects, from 18-67 years old (51 males and 52 females). We found a large and highly significant interindividual variability in the activity of all the AOE studied (p < 0.001). The interindividual coefficients of variation were 13.5% for SOD, 21.0% for CAT, and 36.2% for GSH-Px, indicating that GSH-Px exhibits the highest interindividual variability. Females showed higher SOD (p < 0.001) and CAT (p < 0.001) activities but lower GSH-Px (p < 0.05) activity than males. We found a significant effect of age on SOD activity (p < 0.001), showing that in human blood it decreases with age and that this decrease is not linear, beginning at 28 years of age. We also observed a linear effect of age on GSH-Px activity indicating that the activity of this enzyme increases with age (p < 0.01). No effect of age on CAT activity was observed (p > 0.05). AOE activity in smokers was found not to be significantly different from that observed in non-smokers (p > 0.05) except in the case of CAT activity in females, which was found to be lower in smokers than in non-smokers (p < 0.05). In addition, we determined reference ranges for the activity of each antioxidant enzyme studied. Our results confirm that AOE activity in human blood exhibits a wide interindividual variability and suggest that this variability may be ascribed, at least in part, to the sex and age of the individuals. Moreover, our results suggest that cigarette smoking does not influence AOE activity in human blood. Accordingly, it is suggested that for clinical purposes it may be necessary to consider the sex and age of the subjects involved in the study.

Reference ranges of normal blood catalase activity and levels in familial hypocatalasemia in Hungary

In 1756 healthy individuals the mean and S.D. values of blood catalase activity were 113.3±16.5 MU/1 with lower blood catalase for females (107.7±14.4 MU/1, n=880) than for males (117.9±16.8 MU/1, n=876) while the ratios of blood catalase activity to blood hemoglobin concentration were not different (0.841±0.107 MU/g versus 0.849±0.119 MU/g). The decrease of blood catalase with age was greater in males ( b = - 0.084 MU/1 year) than in females ( b = - 0.016 MU/1 year). The screening of 3300 healthy citizens for hypocatalasemia yielded six families (0.18%), and three families were identified out of 1630 clinic patients. These nine families revealed 37 hypocatalasemic patients with 57.5±11.7 MU/1 mean and S.D. of blood catalase activity. Similarly to the Japanese and the Hungarian actalasemic patients, the electrophoretic mobilities of catalase in erythrocytes of hypocatalasemic patients were indistinguishable from that of healthy controls.

Time course study of oxidative stress in aorta and heart of diabetic rat.

1. Oxygen free radicals have been suggested to be a contributory factor in complications of diabetes mellitus. In the present study, we investigated the lipid peroxide level [thiobarbituric acid-reactive substances (TBARS)] and activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) in aorta, heart and blood of control and streptozotocin-induced diabetic rats at various stages of development of diabetes (0 to 6 weeks). 2. There was no change in the TBARS levels of aorta, heart and blood in the control group. A significant (P < 0.05) increase in TBARS levels of aorta, heart and blood was observed in the diabetic group. 3. There were no significant changes in the activities of superoxide dismutase, catalase and glutathione peroxidase in the aorta, heart and blood of control rats at all time intervals. In the diabetic group, there was a significant (P < 0.05) increase in the activity of superoxide dismutase and glutathione peroxidase in aorta from the fourth week onwards while the activity of catalase increased at all time intervals. In the heart of diabetic rats, the activity of total superoxide dismutase and Cu-Zn-superoxide dismutase increased significantly (P < 0.05) from the second week onwards while activity of Mn-superoxide dismutase decreased at the fourth week and increased at the sixth week. The activity of catalase and glutathione peroxidase increased significantly (P < 0.05) at all time intervals. In the blood, the activity of superoxide dismutase and glutathione peroxidase increased from the third week while catalase activity increased from the fourth week. 4. The present findings suggest that oxidative stress starts at early onset of diabetes mellitus and increases progressively.

Effects ofCoptis chinensis on lipid peroxidation and antioxidases activity of rats

In order to make a systematic study of the effect of Coptis chinensis on free radicals, the authors used the method that the drug and the brain homogenate of rat were mixed and incubated to investigate the effect of Coptis on lipid peroxidation. The result showed that the malondialdehyde (MDA) product of rat brain homogenate inhibited by 5% Coptis was significantly different from control (P < 0.001). On the basis of the above-mentioned results, the effect of Coptis on lipid peroxidation and diabetes of rats induced by alloxan was investigated. The result showed: (1) The MDA product of both pancreas and liver homogenate in Coptis group was significantly less than that in control and alloxan group (P < 0.01, P < 0.05). (2) Superoxide dismutases (SODs) in erythrocytes activity was the same for all groups (P > 0.50). (3) The blood catalase (CAT) activity in alloxan group markedly decreased compared with control group (P < 0.05), but no significant change between Coptis and alloxan group (P > 0.05). (4) The value of serum glucose in alloxan group was significantly increased in comparing with control group (P < 0.05). There was a trend to decrease the value of serum glucose in Coptis group compared with alloxan group, but no significant difference between two groups (P > 0.05). The experiment indicated that there was very strong inhibitory effect of Coptis to the lipid peroxidation in vitro and in vivo. Coptis could protect rat from diabetes inducing by alloxan and that probably was due to the fact that Coptis was able to inhibit alloxan inducing free radicals.

Antioxidant enzymes in hypercholesterolemia and effects of vitamin E in rabbits

We investigated the effects of high cholesterol diet in the absence and presence of vitamin E on the activity of antioxidant enzymes [superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-P x)] in rabbits. The animals were divided into 4 groups each comprising of 10 rabbits. Group I, regular rabbit chow diet; Group II, regular rabbit chow diet with added vitamin E; Group III, high cholesterol diet; and Group IV, high cholesterol diet + vitamin E. Antioxidant enzymes of blood were measured in each group before and after 1, 2, 3, and 4 months on the experimental diets. The aorta was removed at the end of the protocol for measurement of antioxidant enzymes. There was a decrease in activity of SOD and GSH-P x and an increase in activity of catalase in blood of Group III. Vitamin E produced a decrease in blood SOD, catalase and GSH-P x activity in Group II and prevented the decrease in SOD and GSH-P x activity in Group IV but did not affect the changes in the catalase activity. SOD, catalase and GSH-P x activity of aortae from Group III increased significantly, while catalase activity increased and GSH-P x activity decreased in those from Group II. Vitamin E prevented the cholesterol-induced rise in catalase and GSH-P x activity in aorta but did not prevent the rise in SOD activity. These results suggest that the activity of antioxidant enzymes in blood is affected differently from that in aortic tissue. There appears to be a mutually supportive interaction among the antioxidant enzymes which provide defense against oxidant injury. The protective effects of vitamin E against hypercholesterolemic atherosclerosis may not be due to changes in the antioxidant enzymes but may be mainly mediated through its chain-breaking antioxidant activity.

Chromosomal sensitivity of human lymphocytes to bleomycin: Influence of antioxidant enzyme activities in whole blood and different blood fractions

The activity of the antioxidant enzymes catalase (CAT), peroxidases (POD), and superoxide dismutases (SOD) in whole blood and different blood fractions was analyzed in 20 normal human beings and correlated with the chromosomal sensitivity of lymphocytes to bleomycin (BLM) (measured as frequency of dicentric chromosomes per BLM dose). Our results demonstrate that both the physiologic activities of the enzymes and the chromosomal sensitivity to BLM exhibit an ample and significant interindividual variability. An inverse and linear correlation between chromosomal sensitivity to BLM and the concentration of 1) CAT and POD in plasma and 2) SOD in whole blood, erythrocytes, and plasma was found. On the other hand, the chromosomal sensitivity to BLM showed a direct correlation with the concentration of SOD and POD in mononuclear leukocytes. It is suggested that a determination of antioxidant enzyme (AOE) activities in a given cell population may serve to predict the chromosomal sensitivity to BLM.

RELATIONSHIP BETWEEN BLOOD CATALASE ACTIVITY AND DRINKING HISTORY IN A HUMAN POPULATION, A POSSIBLE BIOLOGICAL MARKER OF THE AFFINITY TO CONSUME ALCOHOL

The relationship between blood catalase activity and alcohol consumption was investigated in a group of Caucasian volunteers (N = 191). Subjects individually attended a 1-hr session, during which they were asked to complete the Michigan Alcoholism Screening Test (MAST) and MacAndrew Scale (MAC), supply information on alcohol consumption (averaged over the most recent and typical 30-day periods: Recent and Typical Q-values) and other drug use by answering the Concordia Alcohol Screening Questionnaire (CASQ), and provide a 100-microliter blood sample from the fingertip. Results showed a significant positive relationship between typical Q-Value and catalase activity (r = 0.43, P less than 0.001), which improved after eliminating multiple drug users from the analysis (r = 0.65, P less than 0.001). Multiple regression analyses showed that catalase activity combined with being male, using cocaine or crack, scoring highly on the MAC scale and having alcohol-related problems (MAST), explained a significant portion of the variance in Typical Q-Value. These results support the notion that catalase activity is a strong positive determinant of alcohol intake and support the hypothesis that the enzyme catalase plays a role in regulating voluntary ethanol consumption.

Biological variability of superoxide dismutase, glutathione peroxidase, and catalase in blood

We studied the biological variability of blood superoxide dismutase (SOD; EC 1.15.1.1), glutathione peroxidase (GPX; EC 1.11.1.9), and catalase (CAT; EC 1.11.1.6) in a sample of 1836 apparently health subjects, ages 4-97 years. SOD and GPX activities were assayed in plasma (P) and erythrocytes (E) by automated methods, and CAT was measured in erythrocytes by a manual technique. No statistically significant variation of these antioxidant enzyme activities according to gender was demonstrated, except for E-GPX, which was slightly but significantly higher in women than in men (P less than 0.001). Activities appear rather stable in adults less than 65 years old, but decrease for most enzymes in the elderly. There is no evidence that weight, blood pressure, or menopause influences the antioxidant enzymes' activities. In girls ages 10-14 years, E-SOD activity is reduced by 16% (P less than 0.05) after menarche. Variations related to smoking and alcohol consumption are slight and concern only P-SOD and P-GPX, respectively. Conversely, intake of some drugs (e.g., anti-inflammatory agents, antidepressants, and thyroid hormones) modifies activity of some of the three enzymes. E-SOD positively correlates with P-SOD (r = 0.216, P less than 0.001) and E-CAT (r = 0.123, P less than 0.001), and E-GPX with P-GPX (r = 0.218, P less than 0.001). Finally, we propose reference intervals for activities of the three antioxidant enzymes in blood in individuals less than 65 years old.

Effect of a protease inhibitor on the stability of catalase in liver and blood from acatalasemic and normal mice.

Effects of Gabexate mesilate (GM) (([ethyl-4-(6-guanidino hexanoyloxy) benzoate] methane sulfonate)), a protease inhibitor, on the activities of catalase in liver, erythrocytes and reticulocytes from acatalasemic mice were examined. Preincubation without GM at 37 degrees C for 160 min lowered the catalase activities of liver, erythrocytes and reticulocytes from acatalasemic mice, to 24%, 40% and 10% of the initial levels, respectively. But, preincubation with GM at 37 degrees C for 160 min delayed the rapid decrease in activities of residual catalases in the liver, erythrocytes and reticulocytes of acatalasemic mice to 65%, 93% and 85% of the initial values, respectively. At 20 degrees C or below, no reduction in catalase activity of reticulocytes from acatalasemic mice occurred with or even without GM. At pH 5.0, the decrease in catalase activity of acatalasemic mice was small both in the presence and the absence of GM. In the alkaline range, the reduction in the enzyme activity of the mutant mice without GM was enhanced with increase in pH values up to 8.5. But the presence of GM during preincubation at pH 7.5, retained the catalase activity of acatalasemic mice, to 64% of the activity at pH 6.5. These data suggest that some factors affected by GM, might be responsible for the low stability and activity of catalase in the acatalasemic mice.

A quantitative genetic analysis of tissue-specific catalase activity inMus musculus

Tissue-specific catalase activity in 3-week-old animals from inbred mouse strains 129/ReJ, BALB/c, C3H/HeAnl/Cas-1b, C3H/HeSnJ, C3H/S, C57BL/6J, and Swiss-Webster was found to be highly variable by analysis of variance (P = 0.01). Appropriate crosses were made among strains which were classified as normal (BALB/c, C3H/HeSnJ, C3H/S), hypocatalasemic (129/ReJ, C57BL/6J), and acatalasemic (C3H/HeAnl/Cas-1b) with respect to blood catalase activity to study the inheritance of the blood, kidney, liver, and lung catalase activity levels in a number of generations (reciprocal F1's, F2, two backcrosses--BC1 and BC2--and some RI lines). Segregation analysis and statistical methods which tested different models of inheritance as well as calculations of heritability were used in an effort to assess and evaluate genetic parameters that affect catalase activity. Results indicate that the inheritance of blood catalase activity in the cross involving acatalasemic and normal (BALB/c, C3H/HeSnJ) strains is compatible with the single-locus difference between the parental strains; however, the difference between the acatalasemic and the hypocatalasemic strain (C57BL/6J) would require additional genetic interaction for a satisfactory explanation. A similar pattern of generalization also applies to the inheritance of kidney catalase activity. The segregation pattern for the liver and lung catalase activity in most crosses is significantly different from the expectations of the single locus model. These results are compatible with the concept that a number of genes must affect tissue-specific catalase activity in mice. These may include previously described (e.g., Ce-1 and Ce-2) or novel genetic regulators/modifiers which interact with a single structural gene (Cas-1) or its product to produce the catalase phenotype characteristic of specific tissues in each strain.

日本人ヒポカタラセミア,マウスヒポカタラセミア,マウスアカタラセミアの血球カタラーゼの比活性度

日本人ヒポカタラセミア,マウスヒポカタラセミア,マウスアカタラセミアの血球カタラーゼの比活性度