Electroencephalographic protective action of pyridoxylate during acute hypoxia and subsequent recovery in the rat.

Pyridoxylase at a concentration of 0.6 mmol/kg body weight injected intraperitoneally in rats, increased the resistance of animals to severe hypoxia (O2:3.2%; N2; 96.

[Experimental study of neural and neuro-muscular conduction during simulated diving in dogs and rabbits: anatomo-pathologic correlations].

Five dogs and twelve rabbits were submitted to simulated diving at 6 ATA (compressed air) and 13-15 ATA (normoxic oxygen + nitrogen). Progressive decompressions were carried on for the first, rapid for the lasts. Motor nerve conduction velocity and nerve-muscle delays were measured.

[Evaluation by electrocorticogram of the protective action of piridoxilate against cerebral hypoxia in rats].

Piridoxilate, at the concentration of 120 mg/kg i.p. in rats, enhanced resistance of these animals to hypoxia (N2 : O2 3,2 %).

What EEG criteria for diving fitness?

The authors have tried to consider EEG criteria applicable to fitness for diving. In a study of 90 professional divers, 37 (41%) displayed patterns susceptible of being interpreted as falling outside of strict normalcy. These patterns have sometimes been considered incompatible with diving, or even pathological by some authors.

[Hyperbaric oxygen: effect of sodium dipropylacetate and dipropylacetamine on convulsion seizures and pulmonary lesions in the mouse].

It was shown that oxygen at high pressure (OHP) induced epileptic seizures and pulmonary damages on mice. Dipropylacetate protected mice against nervous syndrome better than did dipropylacetamide. No significant pulmonary protection was observed with both drugs.

The uptake and efflux of L-phenylalanine and L-tyrosine from rat brain cerebral cortex slices.

The uptake of radioactive l-phenylalanine and l-tyrosine into the tissue water of rat brain cerebral cortex slices was shown to have saturation kinetics. The apparent K(m) for the uptake of l-phenylalanine was 0.86mm and for l-tyrosine was 1.

The uptake and efflux of glycine from rat cerebral-cortex slices.

The kinetics of the influx and efflux of radioactive l-glycine was studied in slices of rat cerebral cortex. The influx showed saturation kinetics and was inhibited by l-alanine. Influx was dependent on the presence of Na(+) ions and a metabolizable substrate.

Hyperbaric oxygen: effects on metabolism and ionic movement in cerebral cortex slices.

The incubation of slices of cerebral cortex under hyperbaric oxygen pressures from 1 to 10 atmospheres in the presence of radioactive glucose, pyruvate, succinate, fumarate, L-glutamate, and gamma-aminobutyric acid causes a marked diminution of tissue oxidative reactions. There is a simultaneous decrease in phosphocreatine and adenosine triphosphate, and a reduction of the apparent intracellular ionic gradients. The increase of lipid peroxides, measured directly, is attributed to the toxic effects of hyperbaric oxygen.

Uptake of monosaccharides by guinea-pig cerebral-cortex slices.

By the use of 1mm-iodoacetate to inhibit glycolysis in guinea-pig cerebral tissue slices, the kinetics of the uptake of monosaccharides on transfer of tissue from 0 degrees to 37 degrees were studied. d-Ribose, d-galactose, d-mannose, l-sorbose, and d-fructose showed diffusion kinetics, whereas 2-deoxy-d-glucose, d-glucose, d-arabinose and d-xylose showed saturation kinetics.