Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.6.1.3 (ATPase)
65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intrafusal muscle fibres of the slow soleus (Sol) and fast vastus lateralis (VL) muscles of the rat were studied histochemically. Serial transverse sections were incubated for the localization of succinate dehydrogenase (SDH), alpha glycerophosphate dehydrogenase (GPD) and adenosine triphosphatase (ATPase). The latter was examined further after preincubation in acidic solution held at either low or room temperature (RT). The bag2 intrafusal fibres in both muscles displayed high regular and acid stable ATPase, but low SHD and GPD activities. Bag1 intrafusal fibres showed low to moderate regular ATPase, a regional heterogeneity after RT acid preincubation (low activity in juxtaequatorial and high in polar zones), moderate SDH, but low GPD reactions. In both muscles the chain fibres usually exhibited high ATPase for both regular and cold acid preincubated reactions, but usually low activity after RT acid preincubation; they had high SDH but variable GPD activities. In Sol muscle, however, approximately 25% of spindles contained chain fibres that showed high acid-stable ATPase reaction after both cold and RT acid preincubation. In contrast, chain fibres in some VL spindles had a characteristically low ATPase reaction even after cold acid preincubation. This study, therefore, has delineated the existence of an inherent heterogeneity among chain fibres (with respect to their histochemical reactions) in muscle spindles located within slow and fast muscles and also between those found within populations of either Sol or VL muscle spindles.
...
PMID:Histochemical heterogeneity of intrafusal muscle fibres in slow and fast skeletal muscles of the rat. 296 70

The response of an established line of non-transformed adult rat liver epithelial cells (ARL 15) to thyroid hormone (T3) (3,5,3'-triiodothyronine) was characterized. Exposure of confluent monolayers to 1.10(-8) M T3 for 3 days increased O2 consumption (QO2) between 14-58%, ouabain-sensitive Rb+ uptake 26%, (Na+ + K+)-ATPase activity 32%, alpha-glycerophosphate dehydrogenase activity 103% and cytochrome oxidase activity 208%. The ARL 15 cells, maintained in continuous culture, therefore, exhibit the hallmarks of an authentic physiological response to thyroid hormone.
...
PMID:The response of an established line of rat liver cells to thyroid hormone. 301 38

Histochemical investigations of Sarcocystis microcysts found in two hindleg muscles of cats were carried out. Genus identification was based on the reinforced cyst membrane structure and its dimensions, the structure of the sarcocysts, and an electron microscopic survey of bradyzoite characteristics. The cyst membrane is partly contributed by the host myofiber, the characteristic histochemical features of which it retains. Materials adjacent to the limiting membrane make it appear thicker than it actually is, particularly when the PAS method as well as techniques for the demonstration of alpha-glycerophosphate dehydrogenase and ATPase activities are used. The ground substance occupying the parasitophorous vacuole is not amorphous and metabolically inert, but rather displays a fairly strong and definite ATPase activity, suggesting a trophic role in the support of metrocytes and zoites embedded therein. Cysts tend to adapt their biochemical characteristics to the particular metabolism of the muscle fibers in which they are located. All of these findings are discussed in terms of host-parasite relationships.
...
PMID:Histochemical study of Sarcocystis sp. intramuscular cysts in gastrocnemius and soleus of the cat. 314 30

Comparisons were made of the histochemical characteristics of skeletal muscle from 10 animal species. The basic comparison was made from the staining patterns for the myofibrillar actomyosin ATPase produced by preincubation of fresh frozen cross-sections of muscle at alkaline pH (10.30) or acid pH (4.60) with those produced by preincubation in media containing Cu2+ at alkaline pH (10.30), near neutral pH (7.40), or acid pH (4.60). Muscle sections were also stained for reduced nicotinamide adenine dinucleotide tetrazolium reductase and alpha-glycerophosphate dehydrogenase to provide an indication of the relative oxidative and glycolytic capacity of the different fiber types. Type II fibers in mixed fibered muscles were either very sensitive, moderately sensitive, or relatively insensitive to inactivation of the myofibrillar actomyosin ATPase after acid preincubation. These fibers were identified as type IIA1, IIA2, and IIA3, respectively. The myofibrillar actomyosin ATPase of the type I fibers of these muscles, with the exception of those in mouse muscle, was activated by pretreatment with acid. A separation of animal species was possible based on the stability of the IIA1 fibers to inclusion of Cu2+ in the preincubation medium. For one group of animals (rat, mouse, monkey, man, dog, rabbit, and cow), a reciprocal relationship existed between lability to acid and stability to Cu2+ for type IIA1 and IIA3 fibers, respectively. For the second group of animals (horse, ass, and cat) there was a parallel relationship between lability or stability of the type IIA1 and IIA3 fibers to pretreatment with either acid or Cu2+.
...
PMID:Comparison of fiber types in skeletal muscles from ten animal species based on sensitivity of the myofibrillar actomyosin ATPase to acid or copper. 315 28

Addition of Ca2+ (0.01-1 mM) to a standard Trypanosoma rhodesiense Mg2+-ATPase assay failed to elicit any increase in activity. However, in the absence of externally added Mg2+ and using calcium-EGTA or calcium-CDTA to precisely maintain free metal ion concentration, it was possible to measure a specific Ca2+-ATPase. Cell fractionation studies revealed this ATPase to be predominantly associated with subcellular particles having an equilibrium density of 1.22 g cm-3 and identified as surface membrane. Using a discontinuous sucrose gradient, a surface membrane enriched (SME) fraction, only slightly contaminated with mitochondria as judged by dichlorophenolindophenol-linked alpha-glycerophosphate dehydrogenase activity, was prepared. The SME fraction exhibited Ca2+-ATPase activity, using 200 nM free Ca2+, of 90 and 21 mU mg-1 protein, respectively, using CDTA and EGTA as buffering ligands. This latter result was most unexpected and indicated that the Ca2+-ATPase, in addition to having no Mg2+ requirement, was inhibited by submicromolar levels of Mg2+. The Ca2+-ATPase was found to have a K0.5 = 128 +/- 22 nM free Ca2+, the response to increasing Ca2+ concentration displaying an extremely high degree of co-operativity (Hill number (nH) = 4.9). The enzyme was found to be highly substrate-specific for ATP with K0.5 = 6.2 +/- 0.61 microM ATP. A Hill plot of the reaction velocity as a function of ATP concentration indicated two substrate binding sites (nH = 1.55). A range of potential modulators of ATPase activity were investigated, with only vanadate (V2O3-8) having any effect: 47% inhibition at 5.0 microM. The Ca2+-ATPase was unaffected by the calmodulin antagonists chlorpromazine (50 microM) and trifluoperazine (50 microM), whilst addition of calmodulin failed to produce any stimulation of activity. It is concluded that the kinetic properties of this ATPase are compatible with a potential role in the regulation of intracellular Ca2+ in bloodstream T. rhodesiense.
...
PMID:A high affinity Ca2+-dependent ATPase in the surface membrane of the bloodstream stage of Trypanosoma rhodesiense. 315 62

The purpose of this study was to determine whether 8-12 wk of endurance training produces biochemical and histochemical adaptations in skeletal muscle in foxhounds. Analyses were performed on samples removed from gastrocnemius, triceps, and semitendinosus muscles of foxhounds before and after a treadmill running program. Biochemical analysis showed that training did not alter the activities of phosphofructokinase, beta-hydroxyacyl-CoA dehydrogenase, succinate dehydrogenase, or total phosphorylase. Histochemical analysis of myofibrillar actomyosin ATPase demonstrated three distinct classes of type II fibers and one type I fiber in the semitendinosus and triceps muscles and two type II and two type I fibers in the gastrocnemius muscle. Fiber type distribution and oxidative and glycolytic potentials, as indicated by nicotinamide adenine dinucleotide tetrazolium reductase or alpha-glycerophosphate dehydrogenase staining intensity, were unaltered by training. Similarly, capillary density, capillary-to-fiber ratios, and capillary area-to-fiber area ratios did not change with training. Thus, unlike humans and other mammals (i.e., rat), these foxhounds did not manifest biochemical or histochemical adaptations in skeletal muscle as the result of endurance training. This is consistent with the results of the study in which endurance training produced a 27% increase in maximal cardiac output and a 4% increase in maximal arteriovenous O2 extraction in foxhounds.
...
PMID:Dynamic exercise training in foxhounds. II. Analysis of skeletal muscle. 316 58

In the present study, fetuses were hypophysectomized (hypox) in utero on d 72 to 74 of gestation with an electrical cauterizing needle. One to six successfully hypox fetuses were removed on d 110 of gestation from each of five gilts. Subcutaneous adipose tissue samples and semitendinosus muscles were obtained from the hypox fetuses and an equal number of control fetuses. Body weights of control fetuses (n = 15; mean +/- SE, 1,195 +/- 33 g) were similar to weights of hypox fetuses (n = 15; 1,179 +/- 67 g). Fat cell size in the middle subcutaneous layer of adipose tissue was increased in hypox fetuses (P less than .01) compared with control fetuses. The number of obvious fat cell clusters (outer layer) in lipid stained sections was reduced (P less than .01) by 50% in hypox fetuses. Histochemical reactions for glucose-6-phosphate dehydrogenase, esterase and lipoprotein lipase (LPL) activities in middle layer cell clusters were considerably enhanced in sections from hypox fetuses compared with sections from controls. Quantitative analysis of percent light transmittance (Zeiss photometer) through LPL-stained cell clusters indicated an increase (P less than .001) in LPL staining in sections from hypox fetuses when compared with sections from control fetuses. Transverse muscle sections (cryostat) from hypox fetuses failed to show normal patterns (as seen in control muscles) of reactions for acid ATPase, malate dehydrogenase (NAD-dependent), NADH-TR and alpha-glycerol phosphate dehydrogenase (without NAD). The number of muscle fibers that were stained for these enzymes was greatly reduced in hypox fetuses compared with control fetuses. The number of lipid positive fibers was also reduced in hypox fetuses compared with control fetuses.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Differentiation of adipose tissue and muscle in hypophysectomized pig fetuses. 357 Oct 30

This work tested whether the membrane electrical properties of cat motoneurons, the contractile properties of their muscle units, and the normal relationships among them would be restored 9 mo after section and resuture of their muscle nerve. Properties of medial gastrocnemius (MG) motor units were examined 9 mo following section and resuture of the MG nerve in adult cats. Motoneuron electrical properties and muscle-unit contractile properties were measured. Motor units were classified on the basis of their contractile properties as type fast twitch, fast fatiguing (FF), fast twitch with intermediate fatigue resistance (FI), fast twitch, fatigue resistant (FR), or slow twitch, fatigue resistant (S) (8, 20). Muscle fibers were classified as type fast glycolytic (FG), fast oxidative glycolytic (FOG), or slow oxidative (SO) on the basis of histochemical staining for myosin adenosine triphosphatase, nicotinamide adenine dinucleotide diaphorase, and alpha-glycerophosphate dehydrogenase (48). Following 9 mo self-reinnervation, the proportions of each motor-unit type were the same as in normal control animals. Motoneuron membrane electrical properties [axonal conduction velocity, afterhyperpolarization (AHP) half-decay time, rheobase, and input resistance] also returned to control levels in those motoneurons that made functional reconnection with the muscle (as determined by ability to elicit measurable tension). The relationships among motoneuron electrical properties were normal in motoneurons making functional reconnection. Approximately 10% of MG motoneurons sampled did not elicit muscle contraction. These cells' membrane electrical properties were different from those that did elicit muscle contraction. Contractile speed and fatigue resistance of reinnervated muscle units had recovered to control levels at 9 mo postoperation. Force generation did not recover fully in type-FF units. The reduced tensions were apparently due to failure of recovery of FG muscle fiber area. Following reinnervation, relationships between motoneuron electrical and muscle-unit contractile properties were similar to controls. This was reflected in a degree of correspondence between motor-unit type and motoneuron type similar to normal units (84 vs. 86%, as defined by Ref. 61). There was a significantly increased proportion of type-SO muscle fibers and a decrease in the fast muscle fibers (especially type FOG) in 9 mo reinnervated MG. Together with the unchanged proportions of motor-unit types, this led to an estimate of average innervation ratios being increased in type-S motor units and decreased in type-FR units.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Properties of self-reinnervated motor units of medial gastrocnemius of cat. I. Long-term reinnervation. 371 73

Fetuses were decapitated in one uterine horn in each of 14 sows at 45 d of gestation. Control (C) and decapitated (D) fetuses were removed by Caesarean section from three sows at 65 d of gestation (total of 10 D and 10 C fetuses), two sows at 85 d (six D and six C fetuses) and nine sows at 110 d (nine C and nine D fetuses) of gestation (Exp. 1). In Exp. 2, four to six fetuses were removed from each of two Ossabaw (O) gilts and three crossbred (C, Landrace X Yorkshire) gilts at 70 d of gestation, from three C and O gilts at 90 d of gestation and from three C and two O gilts at 110 d of gestation. In Exp. 1, one semitendinosis muscle was removed for histochemistry, whereas the contralateral muscle was removed and weighed. A medial portion of biceps femoris muscle was removed and used for histochemistry in Exp. 2. In both experiments, transverse sections (cryostat) of muscle were stained for lipid, glycogen (PAS) and the following enzymes: acid ATPase, NADH-TR, NADPH-TR, malate dehydrogenase (NAD- and NADP-dependent reactions; MDH), succinate dehydrogenase (SDH), alpha-glycerol phosphate dehydrogenase (with and without NAD; alpha-GPDH), isocitrate dehydrogenase (NAD dependent; ICDH), esterase, lipoprotein lipase and lipase. In Exp. 1, body and muscle weights of the two groups were not significantly different (P greater than .05) at 65 d of gestation, whereas D fetuses were smaller and had lighter weight muscles (P less than .05) at 85 d of gestation.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Enzyme histochemical studies in an ontogeny study of muscle development in Ossabaw and decapitated fetuses: cellular reactions. 401 46

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.
...
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


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---