Antihypertensive effect of Co-factors of the synthesis and precursors of nucleic acids in experimental hypertension

, ₁₂, .     

Chromosomes and giemsa-bands of the Idaho spotted ground squirrel,Spermophilus brunneus (Howell)

-Spermophilus brunneus . , 13 18 ,S. brunneus S. townsendii mollis (2n=38) , , ; ;S. brunneus . S. brunneus , Spermophilus.

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Supported by National Science Foundation Grants No. GB32114X and No. GB 29131X, and the Sprague Foundation. We thankD. Pozin for technical assistance.     

Orally administered melatonin stimulates the 3α/β-hydroxysteroid oxidoreductase but not the 5α-reductase in the ventral prostate and seminal vesicles of pinealectomized rats

Summary Pinealectomized rats were treated orally with melatonin (MEL) for 14 days. Prostates and seminal vesicles were investigated for the activity of the 4-3-ketosteroid-5-oxidoreductase (5-R) and of the 3/-hydroxysteroid-oxidoreductase (3-HSO). The activity of the 3a-HSO was significantly stimulated (p<0.01, Friedman test) when compared to controls. The activity of the 5-R did not change significantly.This work was supported by the Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 34 (Endokrinologie).     

Über die Brenzkatechinamine im Froschherzen und in der Froschhaut vor und nach Verabfolgung von α-Methyldopa

Summary (1) The adrenalin of the frog heart was found to be localized mainly in the granular fraction (100,000g). After pretreatment with -methyldopa (-MD), the heart also contained -methyldopamine, -methylnoradrenalin, and -methyladrenalin. (2) -MD caused a maximal expansion of the melanophores. This action was counteracted byl-dopa, which per se caused a contraction of the melanophores. After pretreatment with -MD the skin contained besides adrenalin also -methyldopamine and -methyladrenalin. In addition also 5-hydroxytryptophan expanded the melanophores.     

Monoamine oxidase activity in membrane structures of rat liver cell

, .     

Mass spectrometric determination of the amino acid sequence in arginine-containing peptides

aa, a-a a- a aa - aa a -a .     

Artificial lung ventilation during diaphragmatic paralysis

ÿe , CO₂ . CO₂ ÿe . , ÿe , .     

DNA synthesis and mitoses in atrial myocytes of rats with aortal stenosis

, . 2- , 1,60 ±0,59% , 0,96 ± 0,44% — . ë . , ³- .     

Proteins of venezuelan equine encephalomyelitis virions

. : (. . 59,000–61,000 ), (34,000–38,000) (15,000–18,000).     

Hydra vulgaris ω10-lipoxygenase is used in vivo to synthesize new α-linolenic acid metabolites

Previous studies conducted in cytosolic extracts of the freshwater hydrozoanHydra vulgaris led to the finding of an abundant 11(R)-lipoxygenase catalyzing the peroxidation of polyunsaturated fatty acid (PUFAs) on the tenth carbon atom from the aliphatic end (10 peroxidation). Here we describe experiments aimed at identifying the actual metabolites generated in vivo by such enzymic activity. Homogenates ofH. vulgaris polyps were analyzed by HPLC. This showed the presence of three major components chromatographically identical to three metabolites obtained when incubating the homogenates with exogenous -linolenic acid (-LA). The presence, in extracts of polyps prelabelled with [¹⁴C]--linolenic acid, of radioactive metabolites displaying the same chromatographic properties, substantiated the hypothesis that the natural products isolated in vivo are derived from -LA. Gas chromatographic analyses revealed that this was the most abundant PUFA in both free and phosphoglyceride-bound fatty acid pools. [¹H]-NMR analysis of the endogenous substances, carried out in comparison with products obtained from exogenously incubated -LA, indicated that their structures were those of 9-hydroxy-, 9-hydroperoxy- and 9-keto-octadeca-10E-12Z-15Z-trienoic acids (9--HOTrE,-HPOTrE and-KOTrE).Hydra homogenates transformed 9--HPOTrE partly into 9--HOTrE and partly into 9--KOTrE. Chiral phase HPLC conducted on 9--HOTrE established that this metabolite was composed mostly of theR anantiomer. These observations, and the finding that the presence of exogenous arachidonic acid in incubated homogenates significantly reduces the production of -LA metabolites, provide strong evidence that these compounds are produced by an enzymic activity identical to the previously-describedH. vulgaris (R)-10-lipoxygenase. Further experiments suggested that -LA, acting as the native substrate for this enzyme, is mainly esterified on the 2 position ofHydra phosphoglycerides, and that the production of the -LA metabolites described here for the first time from natural sources, can be potentially enhanced in vivo by stimuli activating phospholipase A₂.     

The peculiarities of capacitance vessel reflex responses

Conclusion Changes of the vessel capacity resulted from the pressor synocarotid reflexes, intestinal chemoreflexes and reflexes from the right atrium or ventricle and electric stimulation of the somatic nerve afferents can be either similarly or differently directed as compared with the responses of the resistance vessels.

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, , , .

     

Changes in the lumen of coronary vessels under oligemic hypotension

Conclusions The decrease of circulating blood volume, resulting in oligemic hypotension, may evoke in anaesthetized cat the active constrictory coronary vessel responses of 2 types, one occuring immediately after start of the hypotension and the other having a significantly prolonged latency.

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, , , , ( 4 ), ( 45 ).

     

Magnug reflexex of the chest musculature in man

, , .     

Studies on carbon turnover in the freshwater snailAncylus fluviatilis (Basommatophora)

Summary Carbon turnover rates of young specimens of the freshwater snailAncylus fluviatilis are nearly equal for all organs, whereas in adult specimens intestinal organs (midgut gland and others) show considerably higher turnover rates than the rest animal (animal without organs of the pallial complex).Supported by the Deutsche Forschungsgemeinschaft.     

Reactive synthesis of DNA and mitotic division in atrial heart muscle cells following ventricle infarction

/- 5 - / . , .     

Effect of some monoamine oxidase inhibitors on deamination of biogenic monoamines by rat liver mitochondrial monoamine oxidase

N--N- MAO , , .     

Separation of rat liver mitochondrial amine oxidases

.     

The effect of chloramphenicol analogs on protein biosynthesis in a cell-freeEscherichia coli B system

a aaa a aa aa a a E. coli aa, a aa aa a , a a aa - a .

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Laboratory of Biological Investigations.

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Laboratory for Chemistry of Antibiotics.     

The effect of protein biosynthesis inhibitors upon the development of cellular membranes hyperpolarization

( , , ) .     

Inhibition of sodium transport in frog skin by cardiac glycosides of different molecular structure

p 19-OM no- . ; — .