Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0242706 (hyperoxia)
 5,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of prolonged exposure (up to 66 hours) to pure oxygen breathing and to short (5-minute) oxygen breathing combined with acceleration (+5Gz) on the surface tension and surface potential of the alveolar washout of the albino rat lungs was determined. Both experimental conditions produced atelectasis and a decrease of the surfactant surface activity. Possible mechanisms of shifts of the surfactant activity under hyperoxia only, and hyperoxia with accelerations are discussed.
 ...
PMID:[Effect of oxygen and hypergravitation on alveolar surfactant]. 58 Oct 62

Inhalation of the equimolecular mixture N2O - O2 rapidly achieves good analgesia in cases of coronary occlusion. This mixture was used with 51 patients (37 to 85 years old) with beneficial results on pain in 4 cases out of 5. This effect can be improved by giving a small amount of pethidine with the inhalation. In this way the respiratory depression of the full dose of narcotic analgesics is avoided. In halation of the mixture does not produce undesirable cardio-circulatory or respiratory changes. The oxygen content of the mixture increases patients' PaO2 without the risk of hyperoxia.
 ...
PMID:[Nitrous oxide analgesia in myocardial infarction (author's transl)]. 60 76

The effect of hyperbaric oxygenation (6 atmospheres) on the content of polyamines spermine and spermidine in the rat brain and liver was studied. A decrease of the spermidine content in the brain and liver during oxygen convulsions and four hours after decompression was revealed. The spermine content in the brain during oxygen convulsions decreased as well, but four hours after decompression it increased significantly not eaching the control level. The spermine content in the liver failed to alter during oxygen convulsions, but the next four hours rose sharply. The role of polyamines in the regulation of protein biosynthetic processes under hyperoxia is discussed.
 ...
PMID:[Spermine and spermidine polyamines in the brain and liver of rats under hyperoxic action]. 62 75

Neonatal rats (4--7 days old) and adult rats (approximately 80 days old) were continuously exposed to either 96--98% oxygen or air. Examination of the lungs of neonatal rats, who survived 5 days of oxygen exposure with no evidence of respiratory distress, showed significant increases in the pulmonary superoxide dismutase (SOD) activity (peak value: 144% of air-exposed controls), glutathione peroxidase (GP) activity (126%), glutathione reductase (GR) activity (122%), reduced glutathione (GSH) level (176%), and glucose-6-phosphate dehydrogenase activity (151%). Adult rats, most of whom succumbed within 3 days of oxygen exposure, did not show any significant increase in the activities of pulmonary SOD, GP, GR, and the level of GSH as compared to the air-exposed adult animals. Glucose-6-phosphate dehydrogenase was significantly elevated in the 72-hr oxygen-exposed adult rats. It is concluded that increases in the lung complement of SOD, GR, GP, and GSH in the neonatal rat during oxygen challenge may provide the mechanism(s) for their increased tolerance to hyperoxia-induced lung injury as compared to the adults.
 ...
PMID:Oxygen toxicity: comparison of lung biochemical responses in neonatal and adult rats. 64 79

The results of the studies on the gas composition and acid-base equilibrium of the blood in patients operated upon under epidural anesthesia have proved the rise of venous hyperoxia and the drop of the gas utilization percentage both in anesthetized and non-anesthetized regions. At the level of the whole organism, however, no essential changes of oxygen metabolism are noted.
 ...
PMID:[Gas composition and acid-base equilibrium of blood of patients operated on under conditions of epidural anesthesia]. 64 85

Effect of hypoxia and hyperoxia on some indexes of energy metabolism was studied in the brain of intact rats and those with preliminarily administered hydrocortisone. So hypoxia (8 and 5.5% of oxygen in the medium) increases considerably the lactate and pyruvate content and has no effect on the oxidation and photophosphorylation in the brain mitochondria. The hyperoxic medium (1 at. abs. for 3-5h) inhibits consumption of oxygen and inorganic phosphate by the brain mitochondria, does not effect the lactate content and lowers the pyruvate level. The preliminary administration of hydrocortisone (1 mg per 100 g) under conditions of hypoxia and hyperoxia leads to the further intensification of the glycolysis independently of the initial level of the process. At the same time hormone administration favours normalization of the oxidative processes in the brain tissue under conditions of hyperoxia.
 ...
PMID:[Characteristics of the intensity of glycolytic and oxidative processes in rat brain tissue under hypoxia and hyperoxia]. 66 25

Activity of glutaminase (both phosphate-dependent and phosphate-independent forms of the enzyme) as well as glutamate decarboxylase activity were studied in hyperoxia (6 ati) and under conditions of protection by means of arginine from the effect of hyperoxia. In hyperoxia activity of phosphate-dependent and phosphate-independent forms of glutaminase was decreased by 45% and 51%, respectively. At the same time, glutamate decarboxylase activity was decreased by 32%. Arginine showed a protective effect, delaying the time of oxygen convulsions onset by 2.5-fold. The low activities of glutaminases were maintained but the glutamate decarboxylase activity was increased and even exceeded the control level by 29%. A mechanism of the protective effect of arginine is discussed.
 ...
PMID:[Protective effect of arginine in hyperoxia. Activity of cerebral glutaminase and glutamate decarboxylase]. 66 82

The breathing patterns after voluntary hyperventilation were determined in 14 healthy young subjects under four different conditions: (1) normoxia, (2) hyperoxia, (3) hypoxia, and (4) sudden administration of oxygen against a background of hypoxia to evaluate the effect of hypoxia on the pattern of the posthyperventilation breathing. Under hypoxia the ventilation in the immediate posthyperventilation period was depressed although no decreased ventilation was observed under hyperoxia or normoxia in this period. Sudden administration of oxygen depressed further the decreased ventilation in the posthyperventilation period.
 ...
PMID:The effect of hypoxia on posthyperventilation breathing. 66 17

Mammalian cells may be protected from damage by hyperoxia through the induction of enzymes that reduce destructive oxygen-free radicals. One such enzyme is superoxide dismutase, which reduces superoxide to form hydrogen peroxide and O2. We studied the concentration of this enzyme in rat alveolar macrophages exposed to 85 to 90 per cent O2 in vitro for as long as 6 days and in macrophages obtained from rats exposed to 85 to 97 per cent O2 in vivo for as long as 7 days. In no case was there an increase in superoxide dismutase in rat alveolar macrophages, despite a doubling of superoxide dismutase in whole lungs of rats exposed to 85 to 90 per cent O2 for 7 days in vivo. We concluded that the macrophage of the adult rat does not defent itself against hyperoxia by the induction of superoxide dismutase and does not participate in the increased superoxide dismutase activity of lungs of these animals exposed to hyperoxia.
 ...
PMID:Absence of inductive effect of hyperoxia on superoxide dismutase activity in rat alveolar macrophages. 67 52

Water-insoluble proteins of rat brain were studied as affected by hyperbaric oxygenation (oxygen pressure 6 at.ga. convulsion state). Solubilization of proteins under effect of hyperoxia and triton X-100 increases by 32-81%. Changes in the amino acidic composition of proteins extracted by 0.5% triton X-100 are characterized by an increase in the amount of aspartic acid, cystin, leucine and isoleucine and by a decrease in the amount of histidine, arginine and methionine. Electrophoresis in 7.5% polyacrylamide gel of proteins in the 0.5% triton X-100 extract showed changes in the number and mobility of protein bands.
 ...
PMID:[Effect of hyperoxia on water-insoluble proteins of the brain]. 68 68


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