Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.15.1 (ACE)
 18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The major role of the corpus luteum is biosynthesis of progesterone. Luteal function has been investigated by following plasma progesterone concentrations and by studying ultrastructural and histochemical changes in corpora lutea. Recently, changes in enzyme activities concerned with formation and degradation of progesterone are taken into investigation in order to understand the regulation of luteal function. In rat ovaries, progestational potency of ovarian secretions has been regulated by the activity of 20 alpha-hydroxysteroid dehydrgoenase (20 alpha-HSD), Which catabolizes progesterone to 20 alpha-hydroxypregn-4-en-3-one, progestatinally inert steroid. In regressing corpora lutea, extensive conversion of progesterone to 20 alpha-hydroxypregn-4-en-3-one occurred with a marked increase in 20 alpha-HSD activity as well as a decrease in plasma progesterone concentrations. On the other hand, histochemical studies of glucose-6-phosphate dehydrogenase (G 6 PDH) and delta5-3beta-hydroxysteroid dehydrogenase (3 beta-HSD) have been investigated without any remarkable changes in corporalutea at their early stages of luteolysis. In the present study the activities of steroidogenic enzymes in corpora lutea of pregnant rats are measured after treatment with a variety of abortifacient drugs, and compared with those in corpora lutea of 1 day post partum rats which showed changes characteristic of spontaneous luteolysis. On days 7 to 9 of pregnancy, Wistar-strain pregnant rats were injected with either prostaglandin F2alpha (PGF2alpha), aminoglutethimide or clomiphene citrate (clomid). Animals were sacrificed 15 to 63 hrs. after the last injection, and implantation sites were inspected. Ovaries were removed, and corpora lutea dissected free, weighed and homogenized. The homogenate was centrifuged at 105,000g for 60 min. The supernatant solution was assayed for the activities of G 6 PDH, 6-phosphogluconate dehydrogenase (6 PGDH), malic enzyme, ATP citrate lysase, 20 alpha-HSD and pyruvate kinase. The pellet fraction was re-homogenized, and centrifugated 2,000 g for 5 min. The supernatant solution was used for the assay of 3 beta-HSD. Complete fetal resorption was observed in all rats treated with PGF2alpha, while 7 out of 15 rats (47%) treated with both PGF2alpha and LH-RH maintained pregnancy. In intact rats after treatment with both drugs, lutein cells showed ultrastructures characteristic for luteolysis, although the degree of luteolysis was greatly diminished compared with PGF2alpha-treated ones. In agreement with these ultrastructural findings, 20alpha-HSD activity in corpora lutea was maintained at a rather low level in intact rats, while it was increased moderately in aborted ones after treatment with both drugs. In PGF2alpha-treated rats, G 6 PDH activity increased to 140% and malic enzyme activity decreased to 27% of the activity in control rats. In aminoglutethimide-treated rats, the activites of G 6 PDH and malic enzyme were decreased, while 2-alpha-HSD activity was maintained at a low level...
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PMID:[Studies on the activities of steroidogenic enzymes in corpora lutea of early pregnant rats treated with abortifacient drugs (author's transl)]. 124 45

The oxidative pentose phosphate pathway is poorly developed in the rat heart compared with other organs, since the activity of glucose-6-phosphate dehydrogenase (G-6-PDH), the first and rate-limiting enzyme of the oxidative pentose phosphate pathway, is low. As a consequence, the available pool of 5-phosphoribosyl-1-pyrophosphate and the rate of adenine nucleotide biosynthesis are limited. Isoproterenol, 24 hours after subcutaneous administration at 0.1, 1, and 25 mg/kg, stimulated the activity of G-6-PDH in whole hearts dose-dependently from 4.3 +/- 0.16 (control) to 6.6 +/- 0.35, 10.3 +/- 0.82, and 11.5 +/- 0.56 units/g protein, respectively. The activity of 6-phosphogluconate dehydrogenase, another of the enzymes in the oxidative pentose phosphate pathway, remained unchanged. G-6-PDH activity started to increase 12 hours after isoproterenol application, when the glycogenolytic and functional response was over, and reached a peak value between 24 and 48 hours. This stimulating effect was also demonstrated in cardiac myocytes that were isolated 28 hours after isoproterenol application. beta-receptor blockade with atenolol reduced the isoproterenol-induced increase in cardiac G-6-PDH activity by 90%. Cycloheximide, which inhibits translation, and actinomycin D, which interferes with transcription, attenuated it by 83% and 78%, respectively. These results indicate that cardiac beta-adrenergic receptors and enzyme protein synthesis are involved in this effect. Other beta-sympathomimetic agents such as dopamine, dobutamine, fenoterol, salbutamol, and terbutaline also stimulated myocardial G-6-PDH activity in a time- and dose-related manner. The calcium antagonist D 600 (gallopamil) reduced the isoproterenol-elicited stimulation by 65%, and verapamil blunted the fenoterol-induced increase by 50%. This suggests that Ca2+ ions also contribute to the stimulation of the cardiac oxidative pentose phosphate pathway.
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PMID:Beta-adrenergic agonists stimulate the oxidative pentose phosphate pathway in the rat heart. 197 8

Within the uterine glands, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the activities of G-6-PDH, 6-PGDH, and cytochrome oxidase increase within secreting cells during the 2nd half of pregnancy. The activities of the other enzymes remained almost unchanged during the period of investigation. The description of our results distinguishes between gland neck, middle, and distal part of the secretory unit, respectively. In general, the enzyme activities are similar within the middle and distal gland segments, but lower in the epithelia of the neck region. The activity of dehydrogenases was medium to intensive within the middle and distal gland segments, but only low to medium within the neck portion. Of the hydrolases, the acid phosphatase, ATPase, leucine aminopeptidase, and beta-galactosidase demonstrated an intensive activity within activity secreting cells. The enzyme activities of the gland epithelia are compared with these of the uterine surface epithelia and the histochemical results are discussed in context with their significance in histiotrophic nutrition.
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PMID:[Enzyme histochemistry of the pig placenta. III. Histotopics of enzymes in the uterine epithelium]. 309 49

Ragland, T. E. (Brandeis University, Waltham, Mass.), T. Kawasaki, and J. M. Lowenstein. Comparative aspects of some bacterial dehydrogenases and transhydrogenases. J. Bacteriol. 91:236-244. 1966.-Twenty-eight diverse bacterial species were surveyed for the activities and coenzyme specificities of four enzymes: isocitrate dehydrogenase (ICDH), glucose-6-phosphate dehydrogenase (G-6-PDH), 6-phosphogluconate dehydrogenase (6-PGDH), and reduced nicotinamide adenine dinucleotide phosphate-nicotinamide adenine dinucleotide (NAD) transhydrogenase (TH). Most of the species that exhibited a nicotinamide adenine dinucleotide phosphate (NADP)-linked ICDH also showed significant TH activity, but there were several which did not. Only one of the organisms tested, Xanthomonas pruni, had an ICDH active with both NAD and NADP; it was devoid of TH activity. Acetobacter suboxydans, which lacks ICDH altogether, also had no TH. Some of the species examined had G-6-PDH or 6-PGDH (or both) of dual coenzyme specificity, but there was no apparent relation between these findings and the presence or absence of TH. The TH reaction was assayed by use of analogues of NAD as acceptors. The bacteria could be divided into two groups on the basis of TH specificity, one group reacting at a much faster rate with the 3-acetylpyridine analogue of NAD than with the thionicotinamide analogue, whereas the converse was true for the other group. A few organisms showed no marked specificity for either analogue. This division of specificity can be related to the currently accepted taxonomic classification of the organisms, although a few apparent anomalies were found.
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PMID:Comparative aspects of some bacterial dehydrogenases and transhydrogenases. 437 10

A biochemical study has been made of the effects of low doses of alpha chlorohydrin on all the glycolytic enzymes and two key enzymes of phosphogluconate pathway i.e. glucose-6-phosphate dehydrogenase (G-6-PDH) and 6-phosphogluconate dehydrogenase (6-PGDH) of rat testis and epididymis. All the glycolytic enzymes of testis and epididymis are decreased after treatment with alpha chlorohydrin. G-6-PDH and 6-PGDH are decreased only in epididymis and not in the testis. LDH, ADH and glucose-6-phosphatase were also studied histochemically to show that the drug affects the glycolytic enzymes of epididymal cells and various testicular cell types of testis. Possible significance of these results is discussed.
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PMID:Effect of low doses of alpha chlorohydrin on the enzymes of glycolytic and phosphogluconate pathways in the rat testis and epididymis. 626 79

In porcine interareolar placental epithelia, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetylhexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, nonspecific esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that most of the enzyme activities remained almost unchanged during the period of investigation. Only G-6-PDH and 6-PGDH activities increased within the uterine epithelium and nonspecific esterase activity within uterine as well as chorionic epithelia during the 2nd half of pregnancy. Within chorionic and uterine epithelia, hydrolases but not dehydrogenases demonstrated a higher activity at the bases of chorionic villi as compared to the apices and flanks of the latter. The action and influence of the demonstrated enzymes on metabolism, energy transfer, secretory, and resorptive activities of chorionic and uterine epithelia are discussed.
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PMID:[Enzyme histochemical studies of the swine placenta. Histoptics of enzymes in interareolar placental epithelia]. 643 35

Gene exchanges between Solanum melongena and its allied relative Solanum aethiopicum are a crucial prerequisite for introgression of useful traits from the allied species into the cultivated eggplant. In order to evaluate the extent of genetic recombination between the 2 species, biochemical and molecular markers were employed. A dihaploid population obtained through anther culture of the corresponding tetraploid somatic hybrids was genetically analyzed. The extent of disomic/tetrasomic inheritance and segregation ratios of 3 isozyme systems and intersimple sequence repeat (ISSR) markers were evaluated. The dihaploids, being derived from microspores, allowed for simple, complete, and accurate analyses. The segregation of 280 ISSR markers (110 aethiopicum-specific, 104 melongena-specific, and 66 monomorphic) were evaluated in 71 dihaploids. According to the genetic constitution (simplex/duplex/triplex), almost 64% of the fragments revealed the tetrasomic and/or disomic inheritance. With regard to the assigned species-specific fragments, 68% and 4% were unambiguously the result of tetrasomic and disomic inheritance, respectively. Twenty-four of the 66 monomorphic ISSRs were inherited according to random chromatid segregation. The phenotypes of glucose-6-phosphate dehydrogenase (G-6-PDH), 6-phosphogluconate dehydrogenase (6-PGDH), and shikimate dehydrogenase (SKDH) were studied in 70 dihaploids and inferences were made about the allelic state of their 5 loci. The isozyme markers segregated in the dihaploids in a distorted manner, their segregations did not fit in with any of the expected segregation ratios. However, tetrasomic inheritance might be suggested for G-6-PDH 2 and SKDH 1 loci. Our results demonstrated that gene exchanges occurred readily in the somatic hybrids between S. melongena and S. aethiopicum gr. Gilo.
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PMID:ISSR and isozyme characterization of androgenetic dihaploids reveals tetrasomic inheritance in tetraploid somatic hybrids between Solanum melongena and Solanum aethiopicum group Gilo. 1824 97

1. All enzymes tested: malate dehydrogenase (MDH), glutamate dehydrogenase (GDH), glucose-6-phosphate dehydrogenase (G-6-PDH), and 6-phosphogluconate dehydrogenase (6-P-GDH)_behaved rhythmically during a period of continuous white light interrupted by darkness. All showed approximately the same frequency of 12-15 h. 2. The enzymes of the tricarboxylic-acid cycle (MDH and GDH) are in phase with each other but are out of phase with those of the oxidative pentose-phosphate pathway (G-6-PDH and 6-P-GDH) which are in turn in phase with each other. 3. GDH appears to be activated by the addition of Hoagland's solution which leads to an overt rhythm 24 h prior to darkness. The rhythms of MDH, G-6-PDH and 6-P-GDH cannot be demonstrated prior to the onset of darkness due to an inhibition of the MDH and pentose-phosphate cycle enzymes by light. 4. The control of the frequency and phase of these rhythms are discussed in relation to a positive correlation of the rhythms in enzyme activity presented here and the rhythms of the pyridine nucleotides presented elsewhere.
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PMID:Endogenous rhythmicity and energy transduction : IV. Rhythmic control of enzymes involved in the tricarboxylic-acid cycle and the oxidative pentose-phosphate pathway in Chenopodium rubrum L. 2445 97

In order to study the survival mechanisms to drought stress for fruit body of Auricularia auricula, soluble carbohydrates and respiratory enzymes were investigated. Fruit bodies were exposed to sunlight and were naturally dehydrated. Samples were taken at different levels of water loss (0%, 10%, 30%, 50% and 70%) to measure the content of soluble sugars and polysaccharides. The activities of phosphoglucose isomerase (PGI), combined glucose-6-phosphate dehydrogenase (G-6-PDH) and 6-phosphogluconate dehydrogenase (6-PGDH), and malate dehydrogenase (MDH), were also determined. The results showed that with the increase in water loss, soluble sugars and MDH activity declined, whereas the activities of G-6-PDH and 6-PGDH increased. Soluble polysaccharides content and PGI activity decreased with water loss up to 30% and increased afterwards. These results suggested that the pentose phosphate pathway (PPP), as demonstrated by activities of G-6-PDH and 6-PGDH, could be one of the mechanisms for survival during drought stress in the fruit body of A. auricula. Moreover, soluble polysaccharides may play a part in protecting the fruit body in further drought stress.
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PMID:Impacts of drought stress on soluble carbohydrates and respiratory enzymes in fruit body of Auricularia auricula. 2601 13