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

It was investigated whether rat hepatocytes maintain their plasma membrane specialization (sinusoidal, lateral and bile canalicular sites) and their intracellular polarity (peribiliary region, rich in lysosomes and poor in mitochondria) after isolation. The morphology of the hepatocytes and the cytochemical localization of marker enzymes for the bile canalicular membrane (alkaline phosphatase, adenosine triphosphatase and 5' nucleotidase), for the lysosomes (acid phosphatase) and for the mitochondria (beta-hydroxybutyrate dehydrogenase and succinate dehydrogenase) were studied in situ and directly after isolation using both light and electron microscopy. The morphology of the cells and the cytochemical activity of acid phosphatase, succinate dehydrogenase and beta-hydroxybutyrate dehydrogenase showed that in isolated cells, as in situ, the lysosomes were concentrated in bands, devoid of mitochondria. Unlike in situ the reaction product of alkaline phosphatase, adenosine triphosphatase and 5'nucleotidase was evenly distributed along the entire plasma membrane of the isolated cells. Morphologically, no tight or gap junctions or desmosomes could be detected in the isolated cells, while the plasma membrane appeared to be homogeneously covered with uniform microvilli. In conclusion it can be stated that during isolation the hepatocytes loose their distinct plasma membrane specialization, but maintain their peribiliary region rich in lysosomes and poor in mitochondria.
 ...
PMID:Plasma membrane specialization and intracellular polarity of freshly isolated rat hepatocytes. 627 81

The effects of polychlorinated biphenyls (PCBs) on the development of several intestinal and serum marker enzymes have been studied. The three congeners 4-monochloro (1-CB), 3, 4, 3',4'-tetrachloro (4-CB), and 2, 4, 5, 2', 4, 5'-hexachloro (6-CB) biphenyl were administered orally to pregnant rats on d 8, 11, 13, 15, and 18 or gestation. 1-CB and 6-CB were intubated at doses of 30 mg/kg.d (total dose, 150, mg/kg) and 4-CB was administered at 3 mg/kg-d (total dose, 15 mg/kg). Levels of intestinal alkaline phosphatase, monoamine oxidase, and Na+, K+-adenosin-5'-etriphosphatase and levels of serum alkaline phosphatase, sorbitol dehydrogenase, and beta-hydroxybutyrate dehydrogenase were measured in the dams after weaning and in their offspring at -1, 6, 20, and 55 d of age. Intestinal alkaline phosphatase activity was elevated at the later postnatal stages in the 1-CB group and depressed at 55 d in the 4-CB group, whereas serum alkaline phosphatase levels were markedly depressed prenatally and postnatally in the 4-CB and 6-CB groups, respectively, Intestinal monoamine oxidase levels were markedly increased in the 6-CB group at -1, 6, and 20 d of age and significantly depressed in the 4-CB animals at -1 and 55 d of age. There was an increase in monoamine oxidase activity in the 4-CB group at 6 d. The 1-CB group exhibited depression of monoamine oxidase levels at 6 and elevation at 20 and 55 d. Intestinal Na+, K+-ATPase levels were elevated throughout development in the 1-CB animals and at -1 and 6 d in the 4-CB group. The 6-CB animals showed elevated levels of Na+, K+-ATPase only at 6 d. Serum beta-hydroxybutyrate dehydrogenase and sorbitol dehydrogenase were induced prenatally in the 4-CB animals but enzyme activities decreased to normal by 55 d of age. Significant depression of activity was evident in the 1-CB and 6-CB groups at -1 d in both enzymes. Dams in the 1-CB group showed significant changes in intestinal monoamine oxidase, serum sorbitol dehydrogenase, and serum alkaline phosphatase. Serum levels were elevated in the 4-CB group. Activities of intestinal enzymes remained unchanged in the 4-CB group. All maternal enzyme levels monitored were not significantly changed in the 6-CB group.
 ...
PMID:Effects of polychlorinated biphenyls on the development of intestinal and serum marker enzymes. 627 53

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.
 ...
PMID:[Enzyme histochemical studies of the swine placenta. Histoptics of enzymes in interareolar placental epithelia]. 643 35

The profiles of fiber types in hindlimb muscles from the tree shrew (Tupaia glis), lesser bushbaby (Galago senegalensis), and the slow loris (Nycticebus coucang) were determined using histochemical techniques. Fibers were classified as fast-twitch oxidative-glycolytic (FOG), fast-twitch glycolytic (FG), slow-twitch oxidative (SO), or fast-twitch oxidative (FO), according to reactions for alkaline-stable ATPase, acid-stable ATPase, alpha-glucan phosphorylase, reduced nicotinamide adenine dinucleotide diaphorase, succinate dehydrogenase, mitochondrial alpha-glycerophosphate dehydrogenase (MaGPDH), and beta-hydroxybutyric dehydrogenase, as well as glycogen staining by the periodic acid-Schiff technique. Prolonged dissection of numerous muscles was carried out on hindlimbs submersed in cold Tyrode's solution; such treatment had no qualitative effect on enzyme staining reactions, but it is not a suitable procedure if one wishes to stain for glycogen. Fast-twitch oxidative (FO) fibers are alkaline-stable ATPase-positive and possess low MalphaGPDH enzyme activity. These fibers have not been reported previously in any hindlimb muscles. No muscles of any species studies were homogeneous with respect to fiber type. Slow loris muscles lacked FG fibers. The majority of the muscles of the slow loris contained numerous SO fibers. The relationship between enzyme activities and locomotor pattern is discussed.
 ...
PMID:Comparative histochemical study of prosimian primate hindlimb muscles. I. Muscle fiber types. 645 15

The mechanisms and myocardial alterations associated with NO-deficient hypertension are still far from clear. The aim of the present study was to focus on the enzyme histochemical and subcellular changes in the heart of L-NAME treated rats, as well as to examine the influence of captopril treatment. Wistar rats were administered either L-NAME (40 mg/kg/day) alone or together with captopril (100 mg/kg/day) for a period of 4 weeks. A significant increase of blood pressure confirmed the reliability of the model. The results showed that long-lasting L-NAME administration was accompanied by a decrease of endothelial NO-synthase activity and by a significant local decrease of the following enzyme activities: capillary-related alkaline phosphatase, 5'-nucleotidase and ATPase (but not dipeptidyl peptidase IV) and cardiomyocyte-related glycogen phosphorylase, succinic dehydrogenase, beta-hydroxybutyrate dehydrogenase and ATPases. No activity of these enzymes was found in the scar, whereas a marked increase of alkaline phosphatase and dipeptidyl peptidase IV activities was found in the foci of fibrotization. Histochemical changes correlated with subcellular changes, which were characterized by 1) apparent fibroblast activation associated with interstitial/perivascular fibrosis, 2) heterogeneous population of the normal, hypertrophic and injured cardiomyocytes, 3) enhancement of the atrial granules and their translocation into the sarcolemma, and 4) impairment of capillaries as well as by induction of angiogenesis. Similar alterations were also found in the heart of captopril co-treated rats, despite of the significant suppression of blood pressure. The results indicate that NO-deficient hypertension is accompanied by metabolic disturbances and ultrastructural alterations of the heart and these changes are probably not induced by the renin-angiotension system only.
 ...
PMID:Chronic disturbances in NO production results in histochemical and subcellular alterations of the rat heart. 1080 8

The aim of the present study was to investigate the effects of dietary supplementation with the pyridoindole antioxidant stobadine on histochemical parameters in kidney of streptozotocin-induced diabetic rats. Diabetic male Wistar rats were fed a standard diet or a diet supplemented with stobadine (0.05% w/w) for 24 weeks. The diabetic state was characterized by significantly elevated plasma levels of glucose and glycated hemoglobin, severe reduction of total body weight and relatively enlarged kidneys. Kidney alkaline phosphatase activity was not changed by diabetes. Activity of 5'-nucleotidase, K(+)-dependent p-nitrophenylphosphatase, ATPase and mitochondrial succinic dehydrogenase were markedly decreased in kidneys of diabetic rats. In contrast, activity of beta-hydroxybutyrate dehydrogenase was moderately increased in kidney of diabetic rats as compared to controls. Long-term treatment of diabetic animals with stobadine attenuated histochemical changes in kidney tissue.
 ...
PMID:The pyridoindole antioxidant stobadine attenuates histochemical changes in kidney of streptozotocin-induced diabetic rats. 1255 12

In order to investigate the metabolic poise of the elasmobranch rectal gland, we conducted two lines of experimentation. First, we examined the effects of feeding on plasma metabolites and enzyme activities from several metabolic pathways in several tissues of the dogfish shark, Squalus acanthias, after starvation and at 6, 20, 30 and 48 h post-feeding. We found a rapid and sustained ten-fold decrease in plasma beta-hydroxybutyrate at 6 h and beyond compared with starved dogfish, suggesting an upregulation in the use of this substrate, a decrease in production, or both. Plasma acetoacetate levels remain unchanged, whereas there was a slight and transient decrease in plasma glucose levels at 6 h. Several enzymes showed a large increase in activity post-feeding, including beta-hydroxybutyrate dehydrogenase in rectal gland and liver, and in rectal gland, isocitrate dehydrogenase, citrate synthase, lactate dehydrogenase, aspartate amino transferase, alanine amino transferase, glutamine synthetase and Na(+)/K(+) ATPase. Also notable in these enzyme measurements was the overall high level of activity in the rectal gland in general. For example, activity of the Krebs' TCA cycle enzyme citrate synthase (over 30 U g(-1)) was similar to activities in muscle from other species of highly active fish. Surprisingly, lactate dehydrogenase activity in the gland was also high (over 150 U g(-1)), suggesting either an ability to produce lactate anaerobically or use lactate as an aerobic fuel. Given these interesting observations, in the second aspect of the study we examined the ability of several metabolic substrates (alone and in combination) to support chloride secretion by the rectal gland. Among the substrates tested at physiological concentrations (glucose, beta-hydroxybutyrate, lactate, alanine, acetoacetate, and glutamate), only glucose could consistently maintain a viable preparation. Whereas beta-hydroxybutyrate could enhance gland activity when presented in combination with glucose, surprisingly it could not sustain chloride secretion when used as a lone substrate. Our results are discussed in the context of the in vivo role of the gland and mechanisms of possible upregulation of enzyme activities.
 ...
PMID:Metabolic organization and effects of feeding on enzyme activities of the dogfish shark (Squalus acanthias) rectal gland. 1685 77

Experimental metabolic alkalosis is known to stimulate whole-animal urea production and active ion secretion by the rectal gland in the dogfish shark. Furthermore, recent evidence indicates that a marked alkaline tide (systemic metabolic alkalosis) follows feeding in this species and that the activities of the enzymes of the ornithine-urea cycle (OUC) for urea synthesis in skeletal muscle and liver and of energy metabolism and ion transport in the rectal gland are increased at this time. We therefore evaluated whether alkalosis and/or NaCl/volume loading (which also occurs with feeding) could serve as a signal for activation of these enzymes independent of nutrient loading. Fasted dogfish were infused for 20 h with either 500 mmol L(-1) NaHCO3 (alkalosis + volume expansion) or 500 mmol L(-1) NaCl (volume expansion alone), both isosmotic to dogfish plasma, at a rate of 3 mL kg(-1) h(-1). NaHCO3 infusion progressively raised arterial pH to 8.28 (control = 7.85) and plasma [HCO3-] to 20.8 mmol L(-1) (control = 4.5 mmol L(-1)) at 20 h, with unchanged arterial P(CO2), whereas NaCl/volume loading had no effect on blood acid-base status. Rectal gland Na+,K+-ATPase activity was increased 50% by NaCl loading and more than 100% by NaHCO3 loading, indicating stimulatory effects of both volume expansion and alkalosis. Rectal gland lactate dehydrogenase activity was elevated 25% by both treatments, indicating volume expansion effects only, whereas neither treatment increased the activities of the aerobic enzymes citrate synthase, NADP-isocitrate dehydrogenase, or the ketone body-utilizing enzyme beta-hydroxybutyrate dehydrogenase in the rectal gland or liver. The activity of ornithine-citrulline transcarbamoylase in skeletal muscle was doubled by NaHCO3 infusion, but neither treatment altered the activities of other OUC-related enzymes (glutamine synthetase, carbamoylphosphate synthetase III). We conclude that both the alkaline tide and salt loading/volume expansion act as signals to activate some but not all of the elevated metabolic pathways and ionoregulatory mechanisms needed during processing of a meal.
 ...
PMID:Is the alkaline tide a signal to activate metabolic or ionoregulatory enzymes in the dogfish shark (Squalus acanthias)? 1841 54

Rat liver mitochondria isolated in 0.25 M sucrose were osmotically lysed with distilled water. The effect of osmotic lysis on mitochondrial compartmentation was monitored by following the changes in the specific Mg(++)-ATPase and the stimulation of this activity by DNP. Each resuspension in distilled water caused a progressive increase in the specific Mg(++)-ATPase and a decrease in DNP-stimulation. Lysed mitochondria yielded P:O ratios of slightly less than 1.0 when each of the "site-specific" substrates, NADH, D-beta-hydroxybutyrate, succinate, and ascorbate, were oxidized. These data indicate that only site 3 phosphorylation remained undiminished. The crude, lysed mitochondria were subfractionated by centrifugation on linear sucrose density gradients. Assays for protein, malate dehydrogenase, D-beta-hydroxybutyrate dehydrogenase, and succinate dehydrogenase indicated that the inner compartment could be clearly separated from the outer membrane vesicles. The results also suggested that the small vesicle fraction contained a small proportion of vesiculated inner membranes. Inner mitochondrial compartments, "contracted" by preincubation in the presence of ATP, sedimented to a markedly lower density on the gradients than did the unincubated preparations and about 50% of the ghosts showed a highly condensed morphology. In the contracted preparations, relatively low malate dehydrogenase and D-beta-hydroxybutyrate dehydrogenase activities were found in the fractions comprised of the inner compartments. The specific activity and distribution of succinate dehydrogenase were about the same as were found with the unincubated, lysed mitochondria.
 ...
PMID:The effects of osmotic lysis on the oxidative phosphorylation and compartmentation of rat liver mitochondria. 1986 15


<< Previous 1 2