Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have attempted to develop an objective, semiquantitative classification of fiber types in turtle neck and limb muscle using microphotometry and multivariate statistical techniques. We first stained serial sections for myosin adenosine triphosphatase (ATPase) (with acid and alkaline preincubation and without preincubation), NADH-diaphorase, and two glycolysis-associated markers, alpha-glycerophosphate dehydrogenase (alpha-GPDH) and glycogen phosphorylase A (GPA). This allowed us to characterize individual muscle fibers in terms of their contraction speed and metabolic properties. Next we used microphotometry to measure the optical density of the reaction product in each fiber, and we subjected the resulting optical density matrix to cluster and discriminant function analyses in order to assign fibers to groups (fiber types) and to determine which stains contribute most to the distinction between groups. As a control, we processed a well characterized mammalian muscle (rat sternomastoid) simultaneously. Our results suggest that both neck and limb muscle in Pseudemys can best be described as falling into three groups: 1) slow oxidative (SO) fibers; 2) fast oxidative glycolytic (FOG) fibers, with relatively high oxidative and glycolytic capacities; and 3) fast glycolytic (Fg) fibers, with low oxidative, low/intermediate alpha-GPDH, and high GPA activities. These three fiber types differ from like-named types in rat muscle both in the pH lability of their myosins and in their metabolic profiles.
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PMID:Histochemical classification of neck and limb muscle fibers in a turtle, Pseudemys scripta: a study using microphotometry and cluster analysis techniques. 246 78

The purpose of this study was to determine histologically the distribution of microspheres (MSs) (14 micron), and hence the relative distribution of blood flow, in rat plantaris muscle relative to the fiber types (fast-twitch-oxidative-glycolytic [FOG], fast-twitch-glycolytic [FG], and slow-twitch-oxidative [SO]). Three conditions were investigated: 1) preexercise standing; 2) treadmill locomotion at 15 m/min (fast walking); and 3) treadmill locomotion at 60 m/min (moderate galloping). The MS suspension (containing 1 x 10(6) MSs) was infused into the ascending aorta via a catheter in the carotid artery under each of the 3 conditions so that MSs were distributed to the tissues in proportion to their respective blood flows. Sections (20 micron) of the plantaris muscle were cut and assayed for reduced nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) and myofibrillar adenosine triphosphatase (ATPase) activities so the fibers could be typed as SO, FOG, or FG. MSs were located in the NADH-TR sections, and the fibers next to the MSs were classified and counted. The observed numbers of fibers of each type in each condition that were adjacent to MSs were compared to the predicted number of adjacent fibers based on the assumption the MSs were randomly distributed in the tissue. This analysis demonstrated that MSs (and blood flows) were preferentially distributed to SO fibers during preexercise, to SO and FOG fibers during slow locomotion, and to FOG fibers during fast locomotion. The data support the contention that blood flow is distributed in muscles of conscious animals as functions of fiber type and exercise intensity.
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PMID:Distribution of microspheres in plantaris muscles of resting and exercising rats as a function of fiber type. 297 25

Sodium pump activity of blood vessels has been reported to decrease in several animal models of hypertension. We studied sodium-potassium-adenosine triphosphatase (Na-K-ATPase) activity of renal tubular segments in 12-week-old spontaneously hypertensive rats and in age-matched Wistar-Kyoto normotensive rats. The enzyme activity of the individual nephron segments was determined by a microfluorometric assay in which ATP hydrolysis is coupled with NADH oxidation. In the spontaneously hypertensive rats, systolic blood pressure was significantly higher (181 +/- 3 mm Hg) than in the Wistar-Kyoto rats (134 +/- 2 mm Hg). However, there was no difference in mean Na-K-ATPase activity in any of the nephron segments from the spontaneously hypertensive compared with the Wistar-Kyoto group. It is concluded that Na-K-ATPase activity does not change in any of the nephron segments with spontaneous hypertension.
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PMID:Sodium-potassium-adenosine triphosphatase in nephron segments of spontaneously hypertensive rats. 298 96

Potassium secretion and sodium-potassium adenosine triphosphatase (Na-K-ATPase) activity in the distal nephron segments are known to be influenced by the dietary intake of K+. This has been attributed to a change in the plasma aldosterone level, which also influences K+ secretion and Na-K-ATPase activity in the distal nephron. To investigate whether or not dietary K+ can modulate Na-K-ATPase activity in the distal nephron independently of aldosterone, we determined Na-K-ATPase activity in four distinct nephron segments of adrenalectomized (adx) rabbits given four specific diets for 1 wk before experimentation. Na-K-ATPase activity was determined by a fluorometric microassay in which ATP hydrolysis is coupled to NADH oxidation. The nephron segments examined were the distal convoluted tubule (DCT), the connecting tubule (CNT), the cortical collecting duct (CCD), and the outer medullary collecting duct (MCD). All diets were similar in composition except for their K+ contents, which were 100, 300, 500, and 700 meq/kg in groups 1-4, respectively. In these adx animals, Na-K-ATPase activity increased greater than 200% in the CCD as the dietary intake of K+ increased. There was a linear relationship between K+ excretion and the enzyme activity in this segment. There was a 50% increase in Na-K-ATPase activity in the CNT as the dietary intake of K+ increased in adx animals. However, there were no significant differences in Na-K-ATPase activities in the DCT and MCD among the four treatment groups. It is concluded that dietary K+ intake can influence Na-K-ATPase activity in the CCD and CNT independently of plasma aldosterone levels.
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PMID:Renal adaptation to potassium in the adrenalectomized rabbit. Role of distal tubular sodium-potassium adenosine triphosphatase. 299 42

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

Macroscopic, histopathologic, and histochemical investigations were made on a group of eight neonatal Angus X Hereford calves, selected from an ongoing outbreak of crooked calf disease among calving heifers. Arthrogryposis of the forelimbs was seen to varying degrees in all eight animals, and torticollis was present in six calves. Histopathology, using hematoxylin and eosin stain, did not reveal any striking or consistent lesion in the affected animals; the majority of the tissues sampled were normal. Muscle samples were processed for adenosine triphosphatase (ATPase) and NADH-tetrazolium reductase (NADH-tr) histochemistry, and the data suggest that a primary myopathy is not responsible for the congenital anomalies in the affected calves.
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PMID:Crooked calf disease: a histological and histochemical examination of eight affected calves. 381 Nov 38

In porcine areolar placental epithelia, 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, 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 the enzyme activities remained almost unchanged during the period of investigation. Of the dehydrogenases, the diaphorases as well as succinate and lactate dehydrogenase demonstrated generally an intensive activity within the epithelia. The activity of the other dehydrogenases was only low. The activity of unspecific esterase was very intensive within the uterine epithelia but remarkably low within chorionic epithelia. Contrarily, the reaction of adenosine triphosphatase was more intensive within chorionic than uterine epithelia. All investigated glucosidases reacted distinctly positive within chorionic epithelia, but only beta-N-acetyl-hexosaminidase and beta-galactosidase in uterine epithelia. The high activity of acid phosphatase, especially within the chorionic epithelium, seems to be connected with uteroferrin, an iron-binding protein. The histochemical results are discussed in context with the function of the areolae in histiotrophic nutrition and iron transport.
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PMID:[Enzyme-histochemical studies of the pig placenta. II. Histotopics of enzymes in the areolar placenta epithelium]. 392 41

The effects of short- or long-term complete cerebral ischemia were studied in the gerbil brain using a multi-parameter monitoring system. Metabolic (NADH redox state) and hemodynamic responses were monitored by surface fluorometry-reflectometry. Ionic activities (K+ and pH) were measured by surface macroelectrodes. Electrical activity was evaluated by monitoring the general electrocorticogram (ECoG) as well as local DC steady potential (two sites). Two groups of gerbils were studied to compare the effects of 4-5 min occlusions with those of 30 min complete ischemia. During bilateral carotid artery occlusion the cortex is exposed to complete ischemia resulting in the complete depletion of O2 with attendant maximal reduction of NADH. Extracellular K+ began to increase as soon as energy reserves were decreased with a time course suggesting two different kinetic areas. Surface pH decreased very shortly after the occlusion. During the recovery phase, NADH was reoxidized soon after recirculation, whereas the pH and K+ recovery showed a short delay. ECoG did not recover even when all other parameters reached base-line levels. The recovery of all the measured parameters was correlated to the duration of the ischemic insult; i.e., the recovery from 30 min of ischemia took significantly longer than after 5 min of ischemia. We conclude that pH recovery depends on recirculation and adequate O2 supply to the tissue, whereas K+ recovery required not only an adequate O2 supply but also the integrity of the adenosine triphosphatase system.
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PMID:Metabolic, ionic, and electrical responses of gerbil brain to ischemia. 397 Jan 91

1. Assay conditions are described for the ATP-dependent, uncoupler-sensitive, energy-linked reduction of NAD(+) by succinate, dl-alpha-glycerophosphate or d-lactate in membranes from aerobically grown Escherichia coli. 2. The reaction may be demonstrated in electron-transport particles (ET particles) from cells grown in glycerol, but not in depleted particles washed in low-ionic-strength buffer, or in ET particles from cells grown in glucose. 3. The latter two classes of particles have low specific activities of ATPase (adenosine triphosphatase), succinate dehydrogenase, dl-alpha-glycerophosphate dehydrogenase and d-lactate dehydrogenase relative to undepleted ET particles from cells grown in glycerol. 4. Reconstitution of energy-linked NAD(+) reduction in particles from cells grown in glucose was done by: (a) addition of the high-speed supernatant fraction from sonicates of the same cells; (b) addition of a protein fraction, precipitated by (NH(4))(2)SO(4) from this supernatant, or (c) addition of an (NH(4))(2)SO(4)-precipitated fraction from the low-ionic-strength wash of particles from cells grown in glycerol. 5. The use of (NH(4))(2)SO(4)-precipitated fractions from ATPase- or succinate dehydrogenase-deficient mutants grown in glycerol in the above reconstitution indicated that failure to demonstrate the reaction in particles from cells grown in glucose was a result of inadequate activities of appropriate dehydrogenases, rather than of ATPase. 6. Energy-linked NAD(+) reduction could be demonstrated in particles from a ubiquinone-deficient mutant only after restoration of NADH oxidase activity by adding ubiquinone-1. 7. The measured rate of the energy-linked reaction in particles from a haem-deficient mutant, however, was not stimulated after the ATP- and haematin-dependent acquisition of functional cytochromes. 8. Results are interpreted as evidence of the ubiquinone-dependent, but cytochrome-independent, nature of the site I region of the respiratory chain in E. coli.
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PMID:Energy-linked reduction of nicotinamide--adenine dinucleotide in membranes derived from normal and various respiratory-deficient mutant strains of Escherichia coli K12. 415 32

1. One week after denervation several biochemical characteristics of the fast extensor digitorum longus and slow soleus muscles from adult rats were investigated and compared with the characteristics of the corresponding unoperated contralateral muscles. 2. After these short periods of denervation-induced atrophy, the isolated myosins showed unchanged ATPase (adenosine triphosphatase) activities, but there was the expected difference between fast and slow muscle. 3. The specific activities of several soluble enzymes and their characteristic patterns were found to be only slightly modified in both the extensor and soleus muscles after denervation, as were most of the activities measured in the isolated mitochondria. 4. The most significant modifications were in the isolated sarcoplasmic reticulum, and appeared to be specific to either slow or fast muscle. 5. Denervation of slow muscle led to a marked increase of Ca(2+)-transport rates, and of the specific activity of the Mg(2+)-activated K(+)-modulated Ca(2+)-stimulated ATPase, together with changes in the polyacrylamide-electrophoretic profiles of the microsomal membrane protein. Transformation of these several properties of slow muscle sarcoplasmic reticulum to those of fast muscle sarcoplasmic reticulum was further substantiated by electron-microscopic analysis after negative staining. Control experiments with tenotomized soleus muscle gave negative results. 6. The isolated sarcoplasmic reticulum from fast muscle showed a slight diminution of ATPase-linked Ca(2+)-transport activity and a selective increase of rotenone-insensitive NADH-cytochrome c reductase activity, in addition to a greater emphasis on slow-type electrophoretic components of the structural membrane protein. 7. The significance of these results in relation to specific differentiating influences from motor nerves is discussed.
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PMID:Early biochemical consequences of denervation in fast and slow skeletal muscles and their relationship to neural control over muscle differentiation. 426 59


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