Long-term starvation in Xenopus laevis daudin—III. Effects on enzymes in several tissues

• 1.1. Adult, female Xenopus laevis were subjected to 12 months of starvation.
• 2.2. Starvation resulted in a continuous reduction in the activity of both hepatic and renal glucose-6-phosphate dehydroganse.
• 3.3. Fructose-1,6-diphosphatase was significantly reduced at months 10 and 12 in the liver, and at months 4, 10, and 12 in the kidney.
• 4.4. Pyruvate kinase activity of muscle and liver decreased during the experimental period whereas the renal enzyme remained essentially unchanged.
• 5.5. Both hepatic and renal glutamate-pyruvate transaminase (GPT) and hepatic glutamate-oxaloacetate transaminase (GOT) showed a reduction of activity after 2 and 4 months of starvation followed by an increase in GPT but not in GOT.

     

Effect of some--SH and other reagents on aspartate aminotransferase and L-alanine aminotransferase of Paramphistomum explanatum Fischoeder, 1901.

Studies on aspartate aminotransferase (GOT) and L-alanine aminotransferase (GPT) of Paramphistomum explanatum have shown that GPT activity has more than twice the activity of GOT. The effect os some--SH reagents like cadmium, mercury, silver and iodoacetamide revealed that both enzymes were inhibited except that GOT was insensitive to cadmium ions. GPT was found to be much more sensitive to--SH reagents than GOT. There was unusual reaction to the two thiols used, cysteine and mercaptoethanol. Cysteine inhibited both the enzymes and mercaptoethanol activated GPT and inhibited GOT. Thiols in combination with iodoacetamide showed that the strong inhibitory effect of cysteine on both enzymes was reduced by iodoacetamide, but with mercaptoethanol the inhibitory effect on GOT was greater than when either of them was used alone, while GPT the effect of either counteracted each other. EDTA activated both enzymes and partially protected mercury inhibition of both enzymes and silver inhibition GOT only. It provided no protection against silver inhibition of GPT but complete protection of GPT against total inhibition by cadmium ions.     

Studies on glutamic-oxalacetic (GOT) and glutamic-pyruvic (GPT) transaminases of swine kidney worm Stephanurus dentatus (Diesing, 1839). I. Assay and general properties.

Biochemical studies on the two transaminases GOT and GPT of swine kidney worm Stephanurus dentatus have been made. GOT has been found much more active than GPT. Enzyme activities are based on the formation of oxaloacetate (GOT) or pyruvate (GPT) from aspartic acid and alanine respectively with oxoglutarate. A linear relationship is observed between the enzyme concentration and activity. GOT shows a maximum activity at pH 8.0 and Michaelis constant 9 X 10(-3) M for male and 2.9 X 10(-3) M for female. GPT has an optimum pH of 7.5 and a Michaelis constant 19 X 10(-3) M for male and 8 X 10(-3) M for female. The optimum temperature for both GOT and GPT was 60 degrees C.     

Transaminase GOT and GPT activity in extirped sprouts of normal and opaque-2 Maize (Zea mays L.) seedlings

The increased activity of GOT (E.C.2.6.1.1.) and GPT (E.C.2.6.1.2.) transaminases in maize seedlings found as a marker of genotype opaque-2, was investigated in extirped sprouts of both genotypes, normal and opaque-2. The enzymatic activity was determined in three maize samples from breeding experiments, each sample consisting of a genotype pair, normal and opaque-2, collected from segregating ears of maize plants in the S₁ generation. The seedlings were aseptically grown for 7 days in two variants of cultivation, intact seedlings and sprouts extirped after 4 days of germination. In the intact seedlings of genotype opaque-2 an increased activity of GOT and GPT, as compared to the intact normal plants, was observed. The extirpation of the sprouts enhanced GOT and GPT activity in the sprouts of both genotypes. However, in extirped sprouts the GOT and GPT activity was found to be still higher in the genotype opaque-2 as compared with the sprouts of normal genotype. Thus it seems that the increased transaminase activity in the sprouts of genotype opaque-2 is genetically determined. The increase does not result from an induction of enzyme synthesis through the supply of amino acids translocated from the endosperm to the sprouts. The absolute level of transaminases in the different breeding samples is dependent on the parenteral lines, the relative level of GOT and GPT activities is higher in the genotype opaque-2.     

江滩与兴林垦种区钉螺体内几种酶活性的比较

在自动化分析仪上分析了兴林垦种林区内钉螺和草和滩钉螺的总蛋白（ＴＰｒ）含量和谷丙转氨酶（ＧＰＴ）、谷草转氨酶（ＧＯＴ）以及碱性磷酸脂酶（ＡＬＰ）的活力和比活力,及其受林地地下水位高度的影响,结果表明,林地钉螺的ＧＯＴ、ＧＰＴ酶活力和比活力均比滩于钉螺显著提高,ＡＬＰ活力较稳定,但比活力增加,林地内随地下水位降低,钉螺体内总蛋白含量下降,ＧＯＴ、ＧＰＴ比活力均显著升高。     

Pharmacokinetics of Glutamate–Oxaloacetate Transaminase and Glutamate–Pyruvate Transaminase and Their Blood Glutamate-Lowering Activity in Na?ve Rats

Traumatic brain injury (TBI) and stroke lead to elevated levels of glutamate in the brain that negatively affect the neurological outcomes in both animals and humans. Intravenous administration of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) enzymes can be used to lower the blood glutamate levels and to improve the neurological outcome following TBI and stroke. The objective of this study was to analyze the pharmacokinetics and to determine the glutamate-lowering effects of GOT and GPT enzymes in na?ve rats. We determined the time course of serum GOT, GPT, and glutamate levels following a single intravenous administration of two different doses of each one of the studied enzymes. Forty-six male rats were randomly assigned into one of 5 treatment groups: saline (control), human GOT at dose 0.03 and 0.06?mg/kg and porcine GPT at dose 0.6 and 1.2?mg/kg. Blood samples were collected at baseline, 5?min, and 2, 4, 8, 12, and 24?h after the drug injection and GOT, GPT and glutamate levels were determined. The pharmacokinetics of both GOT and GPT followed one-compartment model, and both enzymes exhibited substantial glutamate-lowering effects following intravenous administration. Analysis of the pharmacokinetic data indicated that both enzymes were distributed predominantly in the blood (central circulation) and did not permeate to the peripheral organs and tissues. Several-hour delay was present between the time course of the enzyme levels and the glutamate-lowering effects (leading to clock-wise hysteresis on concentration-effect curves), apparently due to the time that is required to affect the pool of serum glutamate. We conclude that the interaction between the systemically-administered enzymes (GOT and GPT) and the glutamate takes place in the central circulation. Thus, glutamate-lowering effects of GOT and GPT apparently lead to redistribution of the excess glutamate from the brain's extracellular fluid into the blood and can reduce secondary brain injury due to glutamate neurotoxicity. The outcomes of this study regarding the pharmacokinetic and pharmacodynamic properties of the GOT and GPT enzymes will be subsequently verified in clinical studies that can lead to design of effective neuroprotective treatment strategies in patients with traumatic brain diseases and stroke.     

Effect of altered hormonal states on transaminase enzymes in the genital ograns of immature female rhesus monkeys

The effect of ovariectomy and hormone replacement therapy on the activity of glutamate oxalacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) in the oviduct, uterus, cervix and vagina of immature female rhesus monkeys (Macaca mulatta ) was studied. In intact animals, GOT activity was high in the oviduct, whereas GPT was high in the vagina. Ovariectomy suppressed the activity of both the enzymes in varying degrees. Estradiol dipropionate stimulated GOT in the oviduct and uterus, whereas progesterone increased this enzyme in the uterus. Sequential treatment of two hormones inhibited the enzymes in all the tissues; GPT was, however, stimulated in the fundus region of the uterus. The study demonstrated the presence of transaminase enzymes in the genital tissues of rhesus monkey and their differential response to sex steroids.     

Enzyme activities in Pennisetum seedlings germinated in the presence of abscisic and gibberellic acids

Effects of abscisic acid (ABA) and gibberellic acid (GA₃), alone and in combination, on growth and activity of alanine aminotransferase (GPT), aspartate aminotransferase (GOT), and glutamate dehydrogenase (GLDH) were studied in aerial parts of Pennisetum typhoides seedlings. ABA inhibited growth and activity of GLDH, but stimulated the activity of GPT and weakly that of GOT. GA₃, on the other hand, did not affect the activity of any of the enzymes tested, but in combination with ABA tended to antagonise the efrect of the latter.     

Light-stimulation of alanine aminotransferase activity in dark-grown leaves of Lolium temulentum L. as related to chlorophyll formation

Summary The activity of alanine aminotransferase (=glutamate-pyruvate transaminase, GPT) in dark-grown first leaves of Lolium temulentum L. was increased, after an initial lag-phase of 4–6 hr, by more than 130% during the first 24 hr of light-exposure. In comparison, aspartate aminotransferase (=glutamateoxalacetate transaminase, GOT) activity rose by only 18%. Red light treatments of up to 60 min duration produced subsequent increases in GPT activity but the effects were too small to indicate a phytochrome-mediated response. The amounts of enzyme formed were equivalent to those obtained with similar incident intensities of white light. Retuern to darkness after light exposure resulted in an arrestation of the light-stimulated GPT increase. Pre-treatment with cycloheximide caused either stimulatory or inhibitory effects depending upon the concentration applied but, in general, chlorophyll formation and GPT activity responded in a similar manner, whilst GOT showed virtually no response. Chloramphenicol at 6x10^-3 M depressed chlorophyll and Fraction 1 protein synthesis but stimulated GPT activity.The data are discussed in relation to the possible roles of GPT in the leaf. It is suggested that the enzyme, as determined, may be a complex of forms and that at least part of the activity may be involved in the early stages of chlorophyll biosynthesis.     

Enzyme Activities in Urtica dioica: Effects of Daylength and Leaf Age on Glutamate Dehydrogenase, Aspartate Aminotransferase and Alanine Aminotransferase

Enzymes, important to protein synthesis, were investigated in young and old leaves of Urtica dioica. The plants, divided into two groups, were exposed to either 18-hour or 12-hour photo-periods. One group of plants from each photoperiodic regime was subjected to an irradiance of 28 W × m^-2, and the other group of plants to 42 W × m^-2. The enzymes investigated were glutamate dehydrogenase (GDH), aspartate aminotransferase (glutamate-oxaloacetate transaminase, GOT), and alanine aminotransferase (glutamate-pyruvate transaminase, GPT), GDH and GOT were determined by means of electrophoretic separation on polyacrylamide and spectrophotometric measurements. GPT was determined only by the latter method. Plants exposed to 18-hour photoperiods showed much higher GDH activity than did those exposed to 12-hour photoperiods. The activity of GDH also increased with leaf age. Besides one uniform NAD⁺-dependent GDH, two other NAD⁺-independent enzymes, showing GDH activity, were identified on polyacryl-amide gel electrophoresis. The distribution of NADH and NAD⁺-dependent GDH activity between young and old leaves was similar under different growth conditions. The activity of GOT was insensitive to environmental changes. The results regarding GPT indicate that this enzyme responded to different photoperiods in the same way as GDH. A correlation coefficient of 0.928 was obtained for the relationship between GDH and GPT activity.     

Response related enzymatic changes in ovaries of superovulated mice

Adult female mice were superovulated with PMSG followed by HCG and 140 blastocysts and 69 morulae were recovered from 24 mice. On the basis of the response, mice were divided into six groups; non responders, 1-5, 6-10, 11-20, 21-30 and >30 embryos. The ovaries of the animals were pooled group wise, homogenized in PBS (pH 7.4) and after centrifugation for 10-15 minutes, the supernatant was analyzed for the enzymes, guanine oxaloacetate transaminase (GOT), guanine pymvate transaminase (GPT), acid phosphatases (ACP) and alkaline phosphatases (AKP). Acid and alkaline phosphatase activities did not show any variation in relation to response to superovulation but GOT and GPT showed significantly increased activity in response to induction of superovulation. A statistically significant positive correlation was found between GOT and GPT activities and the superovulatory response in mice.     

Determination of the activities of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase in a microfluidic system

A microfluidic system for the analysis of the activities of glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) was fabricated. The device consists of a glass chip with a micro-electrochemical L-glutamate sensor and a polydimethylsiloxane (PDMS) sheet with a Y-shaped micro-flow channel. A sample solution and a substrate solution for the enzymes were introduced from two injection ports at the end of the flow channel. When the flows were stopped, substrates in a solution mixed immediately with either of the enzymes by diffusion in a mixing channel. L-glutamate produced by the enzymatic reaction of GOT or GPT in the flow channel was detected by using the L-glutamate sensor. A distinct current increase was observed immediately after mixing, and the initial slope of the response curve varied in proportion to the activity of GOT or GPT. The relation between the slope of the response curve and the enzyme activity was linear between 7 and 228 U l-1 for GOT and 9 and 250 U l-1 for GPT. The quality of the response curve was improved with an increase in the channel height. The measurement based on the rate analysis in the micro-flow channel facilitated the reduction of the influence of interferents. The influence of the viscosity of the sample solution was also checked for the analysis of real samples. The determination of the enzyme activities was also conducted in a system with micropumps fabricated for a sample injection. Two solutions could be mixed in the mixing channel, and the activity of the enzymes could be measured as in the experiments using microsyringe pumps.     

Changes in nitrogen metabolism enzyme activities ofVicia faba in response to aluminum and cadmium

Nodules of faba bean (Vicia faba L. cv. Giza 3) plants grown in pots containing clay-loam soil for 90 d have an active nitrate reductase (NR), while the leaves did not show detectable activity. Spraying the plant with increasing concentrations of Al³⁺ or Cd²⁺ (0–1000 μM) significantly inhibited the nodules NR activity, the decline being more pronounced in Cd²⁺ treatment. The specific activity of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) were more prominent in the 60- than in 90-d-old plants; GOT was always higher than GPT. Furthermore, GOT was more sensitive to Al³⁺ and Cd²⁺ treatments and its activity was significantly decreased when the metal concentration increased. Also, Cd²⁺ proved to be more effective than Al³⁺ in suppressing the GOT activity in the nodules, with less significant effect observed in the leaves. In contrast, GPT was hardly affected by the various metal treatments, particulary in the leaves.     

A comparative study of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) levels in the saliva of diabetic and normal patients

Diabetes has been reported to affect salivary glands adversely in humans and experimental models. Glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and lactate dehydrogenase (LDH) are salivary enzymes that also are widely distributed in animal tissues. We determined GOT and GPT levels in saliva samples of 100 type 1 and 30 type 2 diabetic patients using reflectance spectrophotometry and compared them to 30 age and sex matched healthy controls. Statistically significant differences were observed in the mean values of GOT and GPT in type 1 diabetics compared to type 2 and control groups. Significantly higher GOT levels were found in the 1–20 year age group of type 1 diabetics. Our findings suggest that salivary gland damage is due to the same immunological attack that affects pancreatic β cells and results in type 1 diabetes.     

Effect of prolonged administration of insecticide (Cyhalothrin/Karate) on the blood and liver of rabbits.

A sublethal dose of Karate administered to rabbits produced a significant increase in the total erythrocyte count and packed cell volume after 15 days of administration, though no significant change was observed after 30 days. The transaminases (glutamate oxaloacetate transaminase, GOT; glutamate pyruvate transaminase, GPT) also increased after 15 days of treatment. The GPT activity increased 119% and 60% after 15 and 30 days, respectively. From amongst metabolites, glucose content increased 17% and 185%, while cholesterol decreased 40% and 66%, and bilirubin 84% and 61%, after 15 and 30 days, respectively. The hepatic AkP activity decreased 30%, while the GPT activity increased 44%. Other enzymes such as AcP, GOT and LDH remained unaffected. The concentration of other metabolites, except for FAA which increased 35%, remained unaffected. Histological changes were marked by atrophied hepatic cells and hypertrophied nuclei and nucleoli. A trend towards necrosis of hepatic cells was also observed. All these results indicate that Karate is moderately toxic to mammals.     

无菌条件下小麦氨基酸态氮及铵态氮营养效应研究

对铵态氮(硫酸铵)、氨基酸态氮(甘氨酸,谷氨酸及赖氨酸)和缺氮无菌砂培条件下小麦单株干物重、全氮量及根、叶谷草转氨酶和谷丙转氨酶活性作了研究．结果表明,铵态氮和氨基酸态氮均可被小麦吸收,且吸收量相当．培养30d后,甘氨酸和谷氨酸处理的小麦干物重显著高于缺氮及铵态氮处理,而铵态氮、赖氨酸及缺氮处理的干物重相近．低浓度铵态氮(0．7mmol·L^1)培养15d的小麦仅根的GPT活性显著高于缺氮处理,而高浓度(35．7mmol·L^1)处理6h对这两种转氨酶活性影响不大.不同种类、不同浓度的氨基酸态氮培养15d或处理6h后,小麦植株根、叶的GOT或GPT活性变化趋势有较大差异,这反映出小麦外源氨基酸主要同化部位及同化量,与氨基酸种类及浓度有较大关系．     

Effect of different extenders on glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) release from frozen buffalo semen

Sixty buffalo semen samples (motility greater than 60%) were frozen in 3 extenders, viz., Tris yolk glycerol (TY-G), Citric acid whey glycerol (CAW-G) and Egg yolk glucose sodium bicarbonate glycerol (EYGSB-G) for studying the release of GOT and GPT enzymes in the extracellular fluid during pre-freezing (after first extension) and post-freezing (15 minutes and 30 days after freezing). Release of GOT and GPT enzymes was less in TY-G than CAW-G and EYGSB-G extenders. Significant differences (P<0.01) in GOT and GPT release were observed between extenders and bulls at various stages of freezing of semen.     

Effect of subtoxic amounts of furan, acetylfuran and methylene chloride on some serum enzymes of rat

Serum transaminases (GOT and GPT) and ornithincarbamyltransferase (OCT) were determined in rats treated with subtoxic doses of furan, acetylfuran, and methylene chloride. Significant increases of all enzymes were observed in methylene chloride treated rats, while only GOT increased in rats treated with acetylfuran and with furan + methylene chloride. Calculation of the GOT/GPT ratios indicated a pattern of toxic hepatitis only for rats treated with acetylfuran and furan + methylene chloride.     

Differential Regulation of Nitrogen Metabolism in the Wild Type and the High-Light-Tolerant Mutant Cells of Anacystis nidulans

The glutamine synthetase activity in the wild type and high-light-tolerant mutant of Anacystis exhibited differential response to the increasing light intensity (2–40 W/m²). As evident from the results, the glutamine synthetase (GS) activity in the wild type is more dependent on respiration, whereas the GS enzyme in the mutant cells derived its carbon and energy from photosynthesis. Further, results revealed that the reduced GS activity in the wild-type cells under the high-light stress was accompanied by high aspartate amino transferase (AST/GOT) activity and low alanine amino transferase (ALT/GPT) activity. On the contrary, high GS activity in the mutant cells was accompanied by low AST/GOT enzyme activity and high ALT/GPT activity. It was inferred that mutant and wild-type cells adapt to the high-light stress by different mechanisms.     

Blood and liver enzymes in rainbow trout (Salmo gairdneri Rich.) with emphasis on their diagnostic use: Study of CCl4 toxicity and a case of Aeromonas infection

The effect of one intraperitoneal injection of 1.33 ml of CCl₄ per kg of fish was studied. Two experimental series were performed and studied for 10 days (with diluent) and 24 h (pure CCl₄) periods. LDH, GOT, GPT, GR, GDH, CPK, G-6-Pase, and AlkPase were studied. The activity of all enzymes in blood increased: LDH (four times the control), GOT (two times), GPT (three times); they reached a maximal activity 12 h after injection of diluted CCl₄. The levels of some enzymes were also examined in the liver. With pure CCl₄, maximal enzyme activity in blood occurred earlier (6 h). A 6 to 10 times increase was observed for GOT, GPT, LDH, GR, and GDH. Histopathological observations were correlated with these enzymes studies.
An Aeromonas disease characterized by the destruction of the dermis, the exposure of the muscle, and by the presence of numerous petechiae in the liver enabled us to examine the relationships between naturally induced tissue damage and enzyme levels in blood. The levels of seven blood enzymes were determined and the most significant modifications were observed for LDH and CPK. which increased their concentration from 3 to 7 times respectively. A pyruvate saturation test demonstrated that LDH was probably from liver as it was observed after CCl₄ poisoning. The contribution of such biochemical studies in fish research is evaluated.