Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vivo administration of testosterone significantly stimulated the activities of cytochrome oxidase, alpha-glycerophosphate dehydrogenase (alpha-GPDH), succinate dehydrogenase (SDH) and adenosine triphosphatase (Mg2+ ATPase), in mitochondria isolated from the liver of G. carnosus. Administration of dehydroepiandrosterone and androstenedione while significantly stimulated the activities of cytochrome oxidase and alpha-GPDH, did not change that of SDH and Mg2+ ATPase. Simultaneous injections of testosterone and actinomycin D or chloramphenicol prevented the testosterone-stimulated activities of all the oxidative enzymes studied. The results clearly document the important stimulatory role of androgens in the regulation of hepatic mitochondrial metabolism in G. carnosus.
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PMID:Androgenic control of hepatic mitochondrial metabolism in an apoda, Gegenophis carnosus (Beddome). 181 79

The role of neuromuscular activity in maintaining the normal enzyme heterogeneity found in a predominantly fast mixed muscle was studied. Enzymatic profiles of single fibers in the adult cat medial gastrocnemius (MG) were examined after almost complete elimination of neuromuscular activity for 6 mo. Inactivity was achieved by spinal cord isolation (SI), i.e., spinal transection at T12-T13 and L7-S1 combined with bilateral dorsal rhizotomy between the two transection sites. Cross-sectional area and succinate dehydrogenase (SDH) and alpha-glycerophosphate dehydrogenase (GPD) activities were determined in a population of fibers identified in frozen serial cross sections. Each fiber was categorized as light or dark on the basis of its staining characteristics for qualitative myosin adenosinetriphosphatase (ATPase), alkaline preincubation, and its reaction to fast and slow myosin heavy chain (MHC) antibodies. SI resulted in a conversion of nearly all light (approximately 36% in the control) to dark ATPase fibers. Virtually all MG fibers in the SI cats reacted with the fast MHC antibody, whereas very few fibers reacted with slow MHC antibody. On the basis of fiber cross-sectional area, it was estimated that the MG atrophied by approximately 10% after SI. Compared with the mean of the dark and light ATPase fibers in control (weighted by the percent fiber type distribution), mean SDH activity was significantly lower (approximately 70%) and mean GPD activity was significantly higher (approximately 120%) in the SI cats. These data indicate that prolonged electrical silence of a mixed fast hindlimb extensor results in virtually all fibers expressing fast MHC as well as oxidative and glycolytic enzyme profiles normally observed in fast glycolytic fibers.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Enzymatic responses of cat medial gastrocnemius fibers to chronic inactivity. 182 90

Wistar male rats were sacrificed at 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, and 21 days, and at 5 and 10 weeks of age. The histochemical differentiation of slow twitch soleus and fast twitch plantaris muscle fibers was examined from the enzyme activities of adenosine triphosphatase (slow- or fast-contracting), succinate dehydrogenase (high- or low-oxidative), and alpha-glycerophosphate dehydrogenase (high- or low-glycolytic). The soleus muscle fibers differentiated into slow-contracting (S) and fast-contracting (F) fibers at 7 days of age. In the plantaris muscle, differentiation into S and F fibers in the deep portion occurred earlier (9 days) than in the superficial portion (11 days). Thereafter, fiber type shifts between S and F were observed in both muscles. Differentiation into fast-contracting oxidative glycolytic (FOG), fast-contracting glycolytic (FG), and slow-contracting oxidative (SO) fibers occurred in both muscles at 15 and 17 days of age. After subdivision into the three fiber types, a type shift from FOG to FG was observed in both the deep and superficial portions of the plantaris muscle.
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PMID:Histochemical differentiation of fibers in the rat slow and fast twitch muscles. 183 78

Histochemical examinations of the paravertebral muscles and physiological studies were conducted on 17 patients affected with idiopathic scoliosis. Muscle specimens were obtained by needle biopsy. The specimens were removed from both sides of the apical vertebra of the curve and from vastus lateralis. Staining was as follows: 1. ATPase myosin; 2. capillary; 3. Periodic Acid-Schiff (PAS) for glycogen; 4. alpha-glycerophosphate dehydrogenase; 5. DPNH diaphorase. The physiological studies comprised maximum oxygen consumption, anaerobic threshold, isometric force of the flexor muscles of the elbow and femoral quadriceps muscle, and the flexibility of the lumbar spine, shoulder and hip joints. The histochemical tests of the paravertebral muscles showed muscles with a prevalently aerobic metabolic potential, with no evidence of myopathic changes. The physiological studies showed that at the stage at which these subjects were examined, scoliosis is an organic, not a systemic disease.
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PMID:Histochemical and physiological studies in idiopathic scoliosis. 211 83

The adaptation of a slow (soleus, Sol) and a fast (medial gastrocnemius, MG) skeletal muscle to spaceflight was studied in five young male rats. The flight period was 12.5 days and the rats were killed approximately 48 h after returning to 1 g. Five other rats that were housed in cages similar to those used by the flight rats were maintained at 1 g for the same period of time to serve as ground-based controls. Fibers were classified as dark or light staining for myosin adenosine triphosphatase (ATPase). On the average, the fibers in the Sol of the flight rats atrophied twice as much as those in the MG. Further, the fibers located in the deep (close to the bone and having the highest percentage of light ATPase and high oxidative fibers in the muscle cross section) region of the MG atrophied more than the fibers located in the superficial (away from the bone and having the lowest percentage of light ATPase and high oxidative fibers in the muscle cross-section) region of the muscle. Based on quantitative histochemical assays of single muscle fibers, succinate dehydrogenase (SDH) activity per unit volume was unchanged in fibers of the Sol and MG. However, in the Sol, but not the MG, the total amount of SDH activity in a 10-microns-thick section of a fiber decreased significantly in response to spaceflight. Based on population distributions, it appears that the alpha-glycerophosphate dehydrogenase (GPD) activities were elevated in the dark ATPase fibers in the Sol, whereas the light fibers in the Sol and both fiber types in the MG did not appear to change. The ratio of GPD to SDH activities increased in the dark (but not light) fibers of the Sol and was unaffected in the MG. Immunohistochemical analyses indicate that approximately 40% of the fibers in the Sol of flight rats expressed a fast myosin heavy chain compared with 22% in control rats. Further, 31% of the fibers in the Sol of flight rats expressed both fast and slow myosin heavy chains compared with 8% in control rats. Immunohistochemical changes in the MG were minimal. These data suggest that the magnitude and direction of enzymatic activity and cell volume changes are dependent on the muscle, the region of the muscle, and the type of myosin expressed in the fibers. Further, the ability of fibers to maintain normal or even elevated activities per unit volume of some metabolic enzymes is remarkable considering the marked and rapid decrease in fiber volume.
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PMID:Metabolic and morphologic properties of single muscle fibers in the rat after spaceflight, Cosmos 1887. 213 39

The metabolic plasticity of single fibers in adult cat medial gastrocnemius (MG) 6 mo after complete spinal cord transection (Sp) at T12-T13 was studied. Some Sp cats were trained to weight support (Sp-WS) 30 min/day beginning 1 mo posttransection. Cross-sectional area, succinate dehydrogenase (SDH), alpha-glycerophosphate dehydrogenase (GPD), and myofibrillar adenosinetriphosphatase (ATPase) activities were determined in fibers identified in frozen serial sections. Fibers were categorized as light or dark based on myosin ATPase staining, alkaline preincubation. The percentage of dark ATPase fibers was higher in Sp and Sp-WS (approximately 85%) than in control (approximately 60%). All dark ATPase fibers reacted positively to a fast myosin heavy chain monoclonal antibody. In both spinal groups, a higher percentage of dark ATPase fibers reacted to both fast and slow myosin heavy chain antibodies than in controls. Neither Sp nor Sp-WS cats showed fiber atrophy. Compared with control, SDH activity was decreased in both fiber types of Sp cats. Daily weight-support training ameliorated this adaptation. There were no differences among the three groups in mean GPD and ATPase activities for either fiber type. There was a slight tendency, however, for spinal cats to have higher GPD and ATPase activities (independent of type) than control, probably reflecting the larger proportion of dark ATPase fibers in these cats. These observations indicate that 6 mo after spinalization in adult cats, some of the fibers of a fast muscle became "faster" and developed oxidative and glycolytic enzyme profiles that normally are exhibited in fast fatigable motor units.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Enzymatic plasticity of medial gastrocnemius fibers in the adult chronic spinal cat. 214 12

This study was designed to determine the effects of reduced neuromuscular activity on the expression of proteins associated with contractile and metabolic functions and the size of single muscle fibers in the cat soleus. Adult cats were spinalized (Sp) at T12-T13 and maintained in a healthy condition for 6 months. Some of the cats were trained to weight-support (Sp-WS) for 30 minutes per day beginning one month posttransection. Cross-sectional area (CSA), succinate dehydrogenase (SDH), alpha-glycerophosphate dehydrogenase (GPD), and myofibrillar adenosine triphosphatase (ATPase) activities were determined in a population of single fibers identified in frozen serial cross-sections. Each fiber was categorized as either light or dark based on its staining density for qualitative myosin ATPase, alkaline preincubation (pH 8.75). The Sp (45%) and Sp-WS (31%) groups had significantly higher percentages of dark ATPase fibers than control (less than 1%). All dark ATPase fibers were shown to react positively for a fast myosin heavy chain monoclonal antibody, while some of these fibers showed a reaction to both fast and slow myosin heavy chain antibodies. Overall mean fiber CSA were significantly smaller (approximately 25%) than control in both Sp groups. In the Sp-WS, but not the Sp cats, the dark fibers were larger than the light fibers (P less than 0.05), suggesting a preferential effect of postural training on the ATPase converted fibers. There were no significant differences among the three groups in any of the mean enzyme activities for either ATPase type fiber. However, there was a general tendency for the Sp cats to have elevated GPD and ATP activities per muscle; this appeared to be directly related to the percentage of fibers staining darkly for myosin ATPase. These data indicate that 6 months after spinalization some of the fibers of the slow muscle developed fast myosin staining patterns and oxidative and glycolytic enzyme profiles that are normally exhibited in fast fatigue-resistant motor units. Periods of daily weight-support appear to ameliorate some of these adaptations to spinalization. Further, the observation that SDH activities are maintained at control values in spinalized adult cats as well as in spinalized kittens (unpublished observations) suggest that, at least in the soleus, skeletal muscle fibers can maintain their oxidative potential even though there is a marked reduction in neuromuscular activity for 6 months.
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PMID:Expression of a fast fiber enzyme profile in the cat soleus after spinalization. 214 97

Chronic infection of woodchucks with woodchuck hepatitis virus (WHV) was associated with the development of hepatitis, foci of altered hepatocytes and hepatocellular adenomas and carcinomas. The cytomorphological and cytochemical analysis permitted the identification of three different types of focal lesions; namely, glycogen-storage foci, mixed-cell foci and intermediate-cell foci, each showing a characteristic pattern. The cells of the glycogen-storage foci had clear to acidophilic cytoplasm, and were overloaded with glycogen. They showed a marked elevation in the activity of glucose-6-phosphate dehydrogenase (G6PDH) and malate dehydrogenase (MDH), increased activity of succinate dehydrogenase (SDH), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glycerol-3-phosphate dehydrogenase (G3PDH), reduction in the activity of glycogen phosphorylase (PHO), glucose-6-phosphatase (G6Pase), adenosine triphosphatase (ATPase) and adenyl cyclase (ADC), and unchanged activity of glycogen synthase (SYN) and gamma-glutamyl transferase (GGT). The mixed-cell foci mainly consisted of basophilic cells poor in glycogen, but were intermingled with cells containing glycogen. These foci were characterized by a marked decrease in activity of PHO, SYN, G6Pase, G6PDH, ATPase and ADC, and increased activity of GGT, SDH, MDH and GAPDH. The intermediate-cell foci consisted of cells with both basophilic and glycogenotic cytoplasmic compartments, and showed a similar enzyme histochemical profile to the mixed-cell foci, with slight differences in the degree of elevation or reduction of some enzymes. The phenotypic similarities and the close spatial relationship between the foci of altered hepatocytes, and the hepatocellular adenomas and carcinomas in WHV-infected woodchucks, suggest that these lesions are preneoplastic. The focal morphological and metabolic aberrations emerging during hepatocarcinogenesis in WHV-infected woodchuck, are in principle similar to those identified in the course of chemical hepatocarcinogenesis in various species. The focal metabolic aberrations apparently represent a general biological response of the liver parenchyma to oncogenic agents and are closely linked to neoplastic transformation of the hepatocytes.
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PMID:Phenotypic patterns of preneoplastic and neoplastic hepatic lesions in woodchucks infected with woodchuck hepatitis virus. 215 41

Administration of different doses of L-thyroxine (T4) and triiodo-L-thyronine (T3) in vivo in G. carnosus stimulated the activities of cytochrome oxidase, alpha-glycerophosphate dehydrogenase (alpha-GPDH), succinate dehydrogenase (SDH), and Mg2+ adenosine triphosphatase (Mg2+ ATPase) and inhibited the activity of malate dehydrogenase (MDH). While a low dose of thiouracil administration produced a stimulatory effect on cytochrome oxidase and alpha-GPDH activities, a higher dose of thiouracil significantly inhibited the activities of cytochrome oxidase, alpha-GPDH, SDH, Mg2+ ATPase, and MDH. Injection of T4 or T3 into thiouracil-treated animals significantly restored the stimulatory effect of thyroid hormones on oxidative enzyme activities. It is suggested that thyroid hormones in vivo increase and that thiouracil decreases the oxidative capacity of hepatic mitochondria of G. carnosus.
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PMID:Stimulation of oxidative metabolism by thyroid hormones in an apodan amphibian, Gegenophis carnosus (Beddome). 216 65

The effects of hypothyroidism and of replacement therapy with T4 or T3 were studied on the enzymatic activities of liver subcellular fractions isolated from Cynomolgus monkeys. Animals were sacrificed 20 days after thyroidectomy. In mitochondria, thyroidectomy decreased significantly the respiratory chain activity (succinate cytochrome c-reductase), the transfer of cytosolic reducing equivalents (glycerol-3-phosphate dehydrogenase) and the phosphorylating capacity (oligomycin-sensitive ATPase and state 3 respiratory rate). The activity of nucleolar and nucleoplasmic RNA polymerases dropped by about 50% in hypothyroid monkeys. In T4 (2.5 micrograms/kg/d) or T3 (1 microgram/kg/d) treated thyroidectomized animals, the iodothyronine concentrations and the activity of mitochondria and nuclei enzymes were halfway between normal and hypothyroid values. Thus, the mitochondrial effects of thyroidectomy in monkey are, as in rat, at least partly secondary to a decrease in nucleocytoplasmic protein synthesis.
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PMID:[Effect of hypothyroidism on mitochondrial energy metabolism and nuclear synthesis of RNA in the liver of Cynomolgus monkeys]. 242 8


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