Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.4.1.1 (pyruvate carboxylase)
 1,516 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A child with lactic acidosis, severe mental and developmental retardation, and proximal renal tubular acidosis is presented. Biopsy and autopsy studies show severe hepatic, renal cortical, and cerebral deficiencies in pyruvate carboxylase (EC 6.4.1.1) activity. The patient had 1.81 +/- 0.20 units/g fresh weight at biopsy and 0.75 +/- 0.07 units/g fresh weight hepatic pyruvate carboxylase activity at autopsy compared with 10.9, 11.3, and 9.5 units/g fresh weight in two autopsy and one biopsy controls, respectively. The patient's renal cortical pyruvate carboxylase activity at autopsy was 0.008 +/- 0.004 units/g fresh weight compared with 5.05 units/g in the autopsy control. The patient had no detectable (less than 0.018 units/g fresh weight) cerebral pyruvate carboxylase activity at autopsy compared with 0.44, 0.53, and 0.695 units/g in the autopsy cerebrum of one human and two rhesus monkeys, respectively. Pyruvate dehydrogenase complex, phosphoenolpyruvate carboxykinase (PEPCK, EC 4.1.1.32), and fructose-1,6-bisphosphatase (EC 3.1.3.11) activities were in the normal range. The patient's urine pH was above 7.9 when the total serum CO2 was greater than 7.8 mM. However, the patient was able to acidify the urine to pH 5.1 when the total serum CO2 was 1.6 mM. The neuropathologic examination of the brain at autopsy revealed no sign of Leigh's disease, although developmental and degenerative lesions were observed. This is the first reported patient with a primary deficiency in hepatic, renal, and cerebral pyruvate carboxylase deficiency in whom the neuropathologic lesions, distinct from those of Leigh's disease, and proximal renal tubular acidosis have both been documented.
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PMID:Pyruvate carboxylase deficiency and lactic acidosis in a retarded child without Leigh's disease. 21 11

Activities of the 4 hepatic gluconeogenic enzymes: glucose-6-phosphatase, fructose-1,6-diphosphatase, pyruvate carboxylase, particulate and cytosolic phosphoenolpyruvate carboxykinase (PEPCK) have been measured in fetal rabbits (22, 25, 28, 30 and 31 days of gestation) and in fasted or suckling newborns (1 and 2 days after birth). Between days 25 and 31 of gestation, fructose 1,6-diphosphatase and particulate PEPCK activities represent 50% of adult (pregnant female) activities, while pyruvate carboxylase is present at adult values during the same period. Glucose-6-phosphatase is low and cytosolic PEPCK absent in fetal liver until 30 days of gestation and increase significantly during the day preceding birth. Al the enzymes show a further increase after birth independently of the nutritional status of the animals (starved or suckling).
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PMID:Perinatal development of glucoeneogenic enzymes in rabbit liver. 22 57

The effect of fasting and fasting and refeeding on hepatic and renal gluconeogenic enzyme activities were studied in six-week-old chickens (Gallus domesticus: New Hampshire male x Columbian female). Hepatic pyruvate carboxylase appeared not to be affected by fasting, but the renal enzyme activity increased in four-day fasted chickens. The hepatic mitochondrial and cytosolic phosphoenolpyruvate carboxykinases were essentially not affected by fasting. The renal mitochondrial phosphoenolpyruvate carboxykinase showed a slight increase in activity only after a four-day fast, but the cytosolic enzyme activity increased markedly already after a two-day fast. Also the activities of the hepatic and renal fructose-1,6-diphosphatase and glucose-6-phosphatase increased markedly on fasting. Refeeding for four days after a four-day fast returned these enzyme activities to near control values.
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PMID:Effect of fasting and fasting and refeeding on hepatic and renal gluconeogenic enzymes in the chicken. 22 47

Intrauterine growth retardation was induced in rats by ligation of the artery of one of both uterine horns. Activities of pyruvate carboxylase, phosphoenolpyruvate carboxykinase, fructose-1,6-diphosphatase and glucose-6-phosphatase in liver were measured at 0, 1, 3 and 6 h after delivery in newborn rats from normal and sham-operated litters, and from ligated and contralateral uterine horns. Lower activities of fructose-1,6-diphosphatase were found in small-for-gestational-age animals in comparison with animals from contralateral horns. When small-for-gestational-age animals were compared with animals from sham litters (which could be regarded as more satisfactory controls), the activities of two other gluconeogenic enzymes (pyruvate carboxylase and glucose-6-phosphatase) appeared to be lower as well. It is concluded that a delay in the development of these gluconeogenic enzymes could play a role in neonatal hypoglycemia in small-for-gestational-age rats.
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PMID:Gluconeogenic key enzymes in normal and intrauterine growth-retarded newborn rats. 23 14

1. Measurements are presented of the activity and intracellular distribution of phosphoenolypruvate carboxykinase, pyruvate carboxylase and NADP-malate dehydrogenase in rat, guinea-pig and rabbit liver and kidney cortex, together with previously obtained measurements of these enzymes in adipose tissue. 2. In all three tissues pyruvate carboxylase activity was greatest in the rat and lowest in the rabbit. 3. Guinea pig and rabbit were very similar to each other with respect to the extramitochondrial-mitochondrial distribution of phosphoenolpyruvate carboxykinase in all three tissues. 4. NADP-malate dehydrogenase was present in all three tissues in the rat, present in kidney cortex and adipose tissue in the guinea pig and absent from all tissues examines in the rabbit.
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PMID:The activities and intracellular distribution of nicotinamide-adenine dinucleotide phosphate-malate dehydrogenase, phosphoenolpyruvate carboxykinase and pyruvate carboxylase in rat, guinea-pig and rabbit tissues. 23 92

1. Isolated kidney tubules from chicken have been used to study the actions of ethanol, ouabain and aminooxyacetate on glucose formation from lactate and pyruvate. 2. In kidney tubules from well-fed chickens the rate of glucose production from lactate was higher than from pyruvate. Ethanol (10 mM) and ouabain (0.1 mM) were found to increase glucose formation from pyruvate but not from lactate. 3. It is concluded that in the presence of ethanol the fluxes of pyruvate through pyruvate dehydrogenase are in favour of the pyruvate carboxylase reaction restricted. 4. Glucose formation from lactate is decreased by aminooxyacetate (0.1 mM) and ouabain (0.1 mM). 5. Aminooxyacetate inhibited glucose formation from lactate, although chicken phosphoenolpyruvate carboxykinase is located intramitochondrially. 6. The results indicate that the effect of aminooxyacetate like that of ouabain is caused by the restricted formation of pyruvate.
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PMID:Regulation of glucose formation from lactate and pyruvate in isolated tubules of chicken kidney. 31 99

Hydrazine (2 mmol/l) and phenelzine (0.5 mmol/l), which are known to produce hypoglycaemia, inhibit glucose formation from lactate in the perfused guinea-pig liver. The hydrazone formed from pyruvate and phenelzine exerted the same effect at concentrations of only 0.05 mmol/l. It is suggested that the hydrazones are the substances which are effective. All these compounds inhibited pyruvate consumption and decreased CO2 production by the perfused liver which, togeteher with the pattern of hepatic metabolite concentrations, indicate that they diminish pyruvate metabolism. None of them influenced the activities in vitro of pyruvate carboxylase, phosphoenolpyruvate carboxykinase and pyruvate dehydrogenase. The hydrazone compound caused an increase of the ATP/ADP ration at lower concentrations and an opposite effect above 0.5 mmol/l. Nialamide, another hydrazine derivative, also reduced hepatic glucoeogenesis but led to a marked decrease in the hepatic ATP/ADP ratio and liver cell respiration accompanied by a rise in the 3-hydroxybutyrate/acetoacetate ratio.
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PMID:The influence of hydrazine, phenelzine and nialamide on gluconeogenesis and cell respiration in the perfused guinea-pig liver. 41 69

Clofibrate was administered in the diet (0.3% w/w) for varying periods of time to normal rats. Rats were killed by decapitation and several biochemical measurements were made. Clofibrate lowered serum levels of cholesterol and triglyceride and produced a kidney hypertrophy; these effects were maximal after 3 days of feeding and persisted for 21 days. Serum clofibric acid levels were highest on the 3rd day and decreased to maintenance levels by the 7th day. Clofibrate markedly increased the activities of glucose 6-phosphatase, pyruvate carboxylase and phosphoenolpyruvate carboxykinase in kidney cortex and the synthesis of glucose from glutamate, lactate, pyruvate, glycerol and malate by kidney cortex slices. Clofibrate treatment did not affect blood pH or bicarbonate levels. It is concluded that clofibrate enhances renal gluconeogenesis in the rat and that the effect is not caused by altering acid-base balance.
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PMID:Renal gluconeogenesis in clofibrate-treated rats. 63 72

1. Measurements have been made of the activities of enzymes of the glycolytic route, the pentose phosphate pathway, the tricarboxylic acid cycle and lipogenesis in liver and adipose tissue from genetically obese (fa/fa) rats and their lean litter mates (fa/ --). The effect of food restriction for a period of three weeks on the enzyme profile of liver and adipose tissue of the obese rat was also studied. 2. The most striking increases in enzyme activity in livers from obese rats were: (a) among enzymes of lipogenesis; ATP-citrate lyase, acetyl-CoA carboxylase, fatty acid synthetase, malate dehydrogenase (decarboxylating) and cytoplasmic glycerolphosphate dehydrogenase; (b) within the pentose phosphate pathway; glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase; (c) within the glycolytic pathway; glucokinase, pyruvate kinase and lactate dehydrogenase. All of these enzymes showed a significant increase in activity on the basis of U/g liver and U/mg DNA. In adipose tissue all the enzymes of lipogenesis, of the glycolytic route, of the oxidative segment of the pentose phosphate pathway and of the tricarboxylic acid cycle were increased when expressed as U/2 fat pads or as U/mg DNA. 3. The restriction of the food intake of obese rats to that consumed by their lean litter mates for periods of three weeks did not produce the expected adaptive decrease in enzymes of lipogenesis; in adipose tissue, only ATP-citrate lyase and malate dehydrogenase (decarboxylating) showed a marked decrease; no significant change was found in adipose tissue or liver of the activities of acetyl-CoA carboxylase and fatty acid synthetase, when expressed on a cell basis (U/mg DNA). The non-oxidative enzymes of the pentose phosphate pathway and enzymes involved in glycerogenesis (pyruvate carboxylase, malate dehydrogenase and phosphoenolpyruvate carboxykinase) all increased in adipose tissue from limit-fed obese rats. 4. The rate of conversion of specifically labelled glucose to (14C)O2 and 14C-labelled lipid by pieces of adipose tissue and by liver slices was also measured. Insulin caused an increase in the conversion of (1-14C)glucose to (14C)O2 and 14C-labelled lipid in obese rats fed ad libitum, limit-fed rats and in their lean litter mates. 5. The results are discussed in relation to the raised insulin and hypothyroid state of the obese rat. The effect of this altered hormonal status on the activity of cyclic nucleotide phosphodiesterases and cellular levels of adenosine 3' :5'-monophosphate and guanosine 3' :5'-monophosphate and guanosine 3' :5'-monophosphate in relation to the obese syndrome is considered.
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PMID:Adaptive responses of enzymes of carbohydrate and lipid metabolism to dietary alteration in genetically obese Zucker rats (fa/fa). 71 Mar 95

Described in this paper is a technique for the determination of pyruvate carboxylase and phosphoenolpyruvate carboxykinase, two key enzymes of gluconeogenesis in swine liver. The technique is based on measurement of radioactively labelled carbon incorporated in the common metabolite, oxalacetate. The optimum measuring conditions to establish the enzymes in liver homogenate and supernatant are reported and compared with data given by other authors. The found parameters of kinetic properties were in good agreement with the findings obtained from purified enzymes from swine liver.
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PMID:[Radiochemical method for the determination of the activity of the gluconeogenetic key enzymes pyruvate carboxylase and phosphoenolpyruvate carboxykinase in swine livers]. 73 19


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