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E Straumann U Keller M Kraenzlin J Girard A Thélin M Arnaud A Perruchoud W Stauffacher 《Experientia》1988,44(2):176-178
To assess the interaction of the two major stress hormones epinephrine and cortisol in the regulation of leucine kinetics in man, epinephrine (50 ng/kg/min) was infused either alone or in combination with cortisol (2 micrograms/kg/min) into two groups of 6 postabsorptive normal male subjects during 180 min. Plasma leucine concentrations decreased by 28% (p less than 0.05) from baseline during epinephrine treatment (plasma levels 515 pg/ml); this was due to a decrease of leucine appearance (determined by 1-13C-leucine infusions) by 23% (p less than 0.025); leucine oxidation decreased by 29% (p less than 0.05). However, when plasma cortisol concentrations were elevated to supraphysiological levels (16.3 mumol/l) during epinephrine administration, the decreases of leucine plasma concentrations, appearance and oxidation were abolished. Plasma glucose and FFA concentrations were similarly elevated during both kinds of treatment. Since leucine appearance represents a measurement of total body protein breakdown and leucine disappearance into non-oxidative pathways reflects protein synthesis, the data indicate that plasma epinephrine concentrations during severe stress exert a protein anabolic effect in man which may counteract catabolic properties of elevated plasma cortisol. 相似文献
374.
L Léger A M Mouren-Mathieu L Descarries 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(21):1523-1526
Monoaminergic neurons in nuclei raphe dorsalis and locus coeruleus of the Cat may be visualized by radioautography after local micro-instillation of tritiated serotonin and noradrenaline. The concomitant administration of the appropriate tracer with the other biogenic amine in non radioactive form permits a specific identification of serotoninergic and catecholaminergic nerve cell bodies. A small contingent of presumptive serotoninergic neurons is thus demonstrated in the region of the locus coeruleus. 相似文献
375.
H Scherrer N G Seidah S Benjannet P Crine M Chrétien 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(5):543-546
We have recently developed methods to identify biosynthetized beta-endorphin and beta-lipotropin (beta-LPH) following incubation of Rat pars intermedia with radioactive amino acids. We used the same approach for rat brain tissue. In the striatum we found a peptide similar to beta-LPH while its identification in hypothalamus was less positive. This is the first demonstration of such biosynthesis and it could well be an important step in determining the biosynthetic patterns of cerebral endorphins and enkephalins. 相似文献
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J Melcer F Melcer-Dauchy R Hasson R Mérard 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(12):965-968
By a laser beam, enamel and dentin are changed into an identical crystalline structure observed in reflected light and described as recrystallisation after fusion. The Vickers pyramidal numbers of these areas are the same as the mature enamel surface (590 VPN). The theoretical calculation proved that after irradiation in enamel there is an elevation of temperature about 2,5 degrees C through 3 mm. These observations suggest that new operative techniques might be possible. 相似文献
378.
S Hauguel L Cédard 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(5):517-520
In immature human placentas, the activity of the I (glucose-6-phosphate-independent) form of glycogen synthase is significantly increased by insulin, glucose and by both compounds associated. In full-term placentas, the same kind of results has been found in each organ studied; due to the great variability observed in synthetase I control activities, the stimulation is significant only in the presence of insulin. 相似文献
379.
G Marquié 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(2):197-200
Administration of gliclazide inhibited the development of aortic and particularly coronary lesions induced by the cholesterol-containing diet; but it did not noticeably affect the evolution of plasma lipid disturbances. 相似文献
380.