Search results for "Barbiturates"

Protection effect of endurance training against reoxygenation-induced injuries in rat heart

1990

Endurance training by swimming (219-229 h) resulted in a significant protection against hypoxia/reoxygenation-induced injuries in Langendorff-perfused rat hearts. The protection was manifested as improved flow characteristics and a smaller release of creatine kinase into the perfusate. The concentration of thiobarbituric acid reactive substances (TBARS) was lower in the trained than in the respective control hearts. The trained hearts also showed a lower reoxygenation-induced increase in TBARS. The myocardium of the right ventricle and that of the left subepimyocardium were the most affected by reoxygenation. The swimming program induced a decrease in the activities of catalase and glutath…

Effect of metal ion catalyzed oxidation of rifamycin SV on cell viability and metabolic performance of isolated rat hepatocytes.

1991

The effect of rifamycin SV on metabolic performance and cell viability was studied using isolated hepatocytes from fed, starved and glutathione (GSH) depleted rats. The relationships between GSH depletion, nutritional status of the cells, glucose metabolism, lactate dehydrogenase (LDH) leakage and malondialdehyde (MDA) production in the presence of rifamycin SV and transition metal ions was investigated. Glucose metabolism was impaired in isolated hepatocytes from both fed and starved animals, the effect is dependent on the rifamycin SV concentration and is enhanced by copper (II). Oxygen consumption by isolated hepatocytes from starved rats was also increased by copper (II) and a partial i…

Intraoperative neuroprotective drugs without beneficial effects? Results of the German Registry for Acute Aortic Dissection Type A (GERAADA).

2013

OBJECTIVES: Cerebral protection during acute aortic dissection Type A (AADA) surgery may be affected by perfusion strategies and ischaemic protective drugs. METHODS: We analysed the impact of intraoperative barbiturate, steroid and mannitol use and adjunctive cerebral perfusion (CP), on 30-day mortality and new postoperative mortality-corrected permanent neurological dysfunction (PNDmc) in the German Registry for Acute Aortic Dissection Type A. RESULTS: Two thousand one hundred and thirty-seven AADA patients were registered over a 4-year period. The overall 30-day mortality was 16.9%, and the overall rate of PNDmc was 10.0%. A total of 48% of patients received no neuroprotective drugs (cont…

Cryopreservation of Escherichia coli K12TG1: Protection from the damaging effects of supercooling by freezing

2015

Injuries in living cells caused by water freezing during a freeze-thaw process have been extensively reported. In particular, intracellular water freezing has long been incriminated in cell death caused by a high cooling rate, but this supposition could not always be demonstrated. This work aims to discriminate the role of water freezing, dehydration and cold-induced injuries in cellular damage occuring during cryopreservation. For this purpose, Escherichia coli K12TG1 suspensions were maintained in a supercooled or frozen state at -20°C for times ranging from 10 min to 5 h. The supercooled state was maintained for a long period at -20°C by applying a non-injurious isostatic pressure (P<40 …

Age-related changes in antioxidant defence mechanisms and peroxidation in isolated hepatocytes from spontaneously hypertensive and normotensive rats

1994

International audience; The effects of age and hypertension on the antioxidant defence systems and the lipid peroxidation in rat isolated hepatocytes were studied. Four different age groups (1, 3, 6 and 12 months) were considered in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats. Age-associated changes were observed on vitamin E status, glutathione (GSH) level, MDA formation and glutathione peroxidase (GSH-Px) activity in both strains. Maximal levels or activities of these parameters were found at 3 and 6 months, except for MDA which was low at 3 months. Then, a fall was observed at 12-month-old compared to 6-month values. In addition, GSH-Px activity was sig…

High Pressure Liquid Chromatographic Analysis of Barbiturates in the Picomole Range by Fluorometry of Their DANS-Derivatives

1974

�ber den Einflu� von Barbituraten, Thiobarbituraten und Barbiturs�ure auf cellul�re Potentiale und Kontraktionen des Meerschweinchenvorhofes

1962

An elektrisch gereizten Meerschweinchen-Vorhofen wurde der Einflus von Hexobarbital, Pentobarbital, Thiopental, Methitural und Barbitursaure auf die cellularen Potentiale und das Mechanogramm vergleichend untersucht. Beiniedrigen Konzentrationen (bei Methitural ab 7 · 10−6 g/ml) verursachen alle Barbiturate und Thiobarbiturate zunachst eine Verlangerung der 90% igen Repolarisationszeit (RZ), bei hohen Konzentrationen (bei Methitural ab 3 · 10−5 g/ml) eine zunehmende Verkurzung der 20%-, 50%- und 90%-RZ. Bei sehr hohen Konzentrationen (bei den Thiobarbituraten ab 8 · 10−5) der Narkotica werden Ruhe- und Umkehrpotential vermindert. Thiobarbiturate bewirken im Vergleich zu Barbituraten eine se…

On the spectral intermediate at 440 nm formed during mixed function substrate oxidation.

1974

Abstract The spectral shoulder formed at 440 nm in microsomes oxidising hexobarbital and other drugs has been investigated and some of its properties characterised. Hexobarbital, pentobarbital, ethylmorphine and barbital produce this shoulder, while acetanilide, aniline, desmethylimipramine, imipramine, metyrapone and SKF 525-A do not. The formation of the 440 nm shoulder depends on the presence of NADPH and oxygen and is reduced in size when NADH is also present. At saturating substrate concentrations the size of the 440 nm shoulder is correlated to the cytochrome P-450 content. The hexobarbital induced shoulder can be inhibited by drug metabolism inhibitors such as metyrapone, imipramine …

The diversity of GABAA receptors. Pharmacological and electrophysiological properties of GABAA channel subtypes.

1998

The amino acid gamma-aminobutyric-acid (GABA) prevails in the CNS as an inhibitory neurotransmitter that mediates most of its effects through fast GABA-gated Cl(-)-channels (GABAAR). Molecular biology uncovered the complex subunit architecture of this receptor channel, in which a pentameric assembly derived from five of at least 17 mammalian subunits, grouped in the six classes alpha, beta, gamma, delta, sigma and epsilon, permits a vast number of putative receptor isoforms. The subunit composition of a particular receptor determines the specific effects of allosterical modulators of the GABAARs like benzodiazepines (BZs), barbiturates, steroids, some convulsants, polyvalent cations, and et…

Spectrofluorimetric Quantification of Malondialdehyde for Evaluation of Cyclooxygenase-1/Thromboxane Synthase Inhibition

1999

The in vitro assay developed by Hartmann and Ledergerber (1995) utilizing the spectrofluorimetric quantification of malondialdehyde after reaction with thiobarbituric acid was modified and used for further investigations. The human whole blood was replaced by a platelet suspension of pig blood, and calcium ionophore A23187 was used instead of collagen for inducing the arachidonic acid cascade. The modified assay represents a simple, time and cost saving method for the evaluation of cyclooxygenase-1/thromboxane synthase inhibition. The reproducibility and comparability of results is given. Additional experiments allow classification of selective phospholipase A2, cyclooxygenase-1, and thromb…