scholarly journals Plasma albumin synthesis during neonatal development of the rat

1967 ◽  
Vol 102 (3) ◽  
pp. 760-762 ◽  
Author(s):  
R. W. Wise ◽  
I. T. Oliver

1. Liver slices were incubated with (14)C-labelled amino acids. Albumin was isolated from the slices by precipitation with specific antibody and the incorporated radioactivity measured. 2. The rate of synthesis was seen to be equal in liver slices from adult and late-stage foetal rats. 3. Synthesis was very high in the pregnant rat (three times the normal adult value) and in the 5-15-day post-natal rat (twice the normal adult value). 4. The post-natal increase may be due to the disappearance of haemopoietic tissue and its replacement by active parenchymal cells.

1961 ◽  
Vol 38 (3) ◽  
pp. 353-360 ◽  
Author(s):  
Bo Hellman ◽  
Stig Larsson

ABSTRACT The in vitro utilization of uniformly 14C-labelled glucose was studied in the pineal body of goats by using a quantitative application of the radio paper-chromatographic technique. The O2 consumption as well as the formation of CO2 and lactic acid from glucose in the incubation medium was comparatively very high in young goats and decreased gradually with increasing age. The same was true for the formation of labelled amino acids. Thus, there were no measurable amounts of radioactive amino acids in goats older than 6 years, while in the animals 1–3 months old no less than 11.7 μg glucose was converted into amino acids per 25 mg wet weight of the pineal body Glutamic acid and alanine were found in the highest amounts among the different amino acids formed from glucose in the youngest age group. There were also appreciable amounts of arginine, glutamine, δ-aminobutyric acid and aspartic acid. Microscopical examination revealed that not only progressive degenerative changes but also a markedly reduced number of parenchymal cells per unit volume, might account for the diminished glucose metabolism found in the pineal body of adult goats. The metabolic findings, especially the very high rate of formation of amino acids from glucose in the youngest animals, are discussed in the light of the result of recent investigations, which suggest secretion of a protein hormone from the non-adult pineal body.


1968 ◽  
Vol 108 (5) ◽  
pp. 741-748 ◽  
Author(s):  
G. Shanmugam ◽  
P. M. Bhargava

1. Rat liver parenchymal cells in suspension are shown to require a higher concentration of actinomycin D than liver slices for equivalent inhibition of the incorporation of [14C]adenine, [14C]uracil and [32P]phosphate into RNA, and of 14C-labelled amino acids into protein; protein synthesis is much less susceptible to actinomycin D inhibition than RNA synthesis in both the tissue preparations. Possible causes for these differences are discussed. 2. The uptake of [3H]actinomycin D in the first few minutes was much greater in the cell suspensions than in the tissue slices; that in the next 1–4hr. was about the same in both the cases. The uptake by both the tissue preparations was at all times proportional to the concentration of the drug within the range 0·5–2·0μg./ml. 3. In the slices actinomycin D taken up initially was concentrated almost exclusively in the nuclei; with time the concentration of the drug in the mitochondria and the supernatant increased more rapidly than in the nuclei though at no stage did it exceed that in the nuclei. In the cell suspension the largest concentration of the drug taken up initially was found in the supernatant; most of the drug taken up subsequently also stayed in the supernatant. 4. When the drug concentration in the incubation medium was 1μg./ml., its concentration within the parenchymal cells in suspension and the parenchymal cells in the slices reached 2·2 and 1·6μg./cm.3 of cellular volume respectively. On average, 7% of the drug was removed from the medium by the cells in suspension and 23% by the cells in the slices; the average ratio of intracellular to extracellular concentration was 2·4 in the former and 2·1 in the latter case.


1963 ◽  
Vol 205 (5) ◽  
pp. 848-856 ◽  
Author(s):  
Jonas E. Richmond ◽  
William C. Shoemaker ◽  
David H. Elwyn

The rates of synthesis of plasma and liver proteins have been measured in the perfused dog liver and intact rat liver by following the rate of incorporation, over short time intervals, of carbon 14-labeled amino acids of known specific activity. The amino acid compositions of the subcellular fractions of dog liver have been determined. The perfused dog liver synthesized plasma albumin at the rate of 12 mg/min per kg liver, and plasma glycoprotein at the rate of 8 mg/min per kg liver. The rate of albumin synthesis is in reasonable agreement with studies using prelabeled albumin. Liver proteins of both rat and dog appear to contain one or more rapidly turning over fractions. Total rates of synthesis of liver proteins were found to be approximately 200 mg/min per kg liver in both species.


1964 ◽  
Vol 42 (1) ◽  
pp. 139-142 ◽  
Author(s):  
S. J. Patrick ◽  
L. C. Stewart

The effects of hypoglycin A on the metabolism of L-leucine-C14, L-alanine-C14, and L-glutamic-acid-C14 by rat liver slices have been investigated. Hypoglycin exerted markedly inhibitory effects on the conversion of leucine-C14 to fatty acid, cholesterol, and CO2. Conversion of alanine-C14 and glutamic acid-C14 to fatty acids was also inhibited by hypoglycin. No effects of hypoglycin on the conversion of C14-amino acids into protein or glycogen were demonstrated.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Howard Gamper ◽  
Haixing Li ◽  
Isao Masuda ◽  
D. Miklos Robkis ◽  
Thomas Christian ◽  
...  

AbstractWhile genome recoding using quadruplet codons to incorporate non-proteinogenic amino acids is attractive for biotechnology and bioengineering purposes, the mechanism through which such codons are translated is poorly understood. Here we investigate translation of quadruplet codons by a +1-frameshifting tRNA, SufB2, that contains an extra nucleotide in its anticodon loop. Natural post-transcriptional modification of SufB2 in cells prevents it from frameshifting using a quadruplet-pairing mechanism such that it preferentially employs a triplet-slippage mechanism. We show that SufB2 uses triplet anticodon-codon pairing in the 0-frame to initially decode the quadruplet codon, but subsequently shifts to the +1-frame during tRNA-mRNA translocation. SufB2 frameshifting involves perturbation of an essential ribosome conformational change that facilitates tRNA-mRNA movements at a late stage of the translocation reaction. Our results provide a molecular mechanism for SufB2-induced +1 frameshifting and suggest that engineering of a specific ribosome conformational change can improve the efficiency of genome recoding.


2000 ◽  
Vol 279 (2) ◽  
pp. E244-E251 ◽  
Author(s):  
Benoît Ruot ◽  
Denis Breuillé ◽  
Fabienne Rambourdin ◽  
Gerard Bayle ◽  
Pierre Capitan ◽  
...  

Plasma albumin is well known to decrease in response to inflammation. The rate of albumin synthesis from both liver and plasma was measured in vivo by use of a large dose ofl-[2H3-14C]valine in rats injected intravenously with live Escherichia coli and in pair-fed control rats during the acute-phase period (2 days postinfection). The plasma albumin concentration was reduced by 50% in infected rats compared with pair-fed animals. Infection induced a fall in both liver albumin mRNA levels and albumin synthesis relative to total liver protein synthesis. However, absolute liver albumin synthesis rate (ASR) was not affected by infection. In plasma, albumin fractional synthesis rate was increased by 50% in infected animals compared with pair-fed animals. The albumin ASR estimated in the plasma was similar in the two groups. These results suggest that hypoalbuminemia is not due to reduced albumin synthesis during sepsis. Moreover, liver and plasma albumin ASR were similar. Therefore, albumin synthesis measured in the plasma is a good indicator of liver albumin synthesis.


2001 ◽  
Vol 100 (4) ◽  
pp. 459-465 ◽  
Author(s):  
Kirsty A. HUNTER ◽  
Peter J. GARLICK ◽  
Iain BROOM ◽  
Susan E. ANDERSON ◽  
Margaret A. McNURLAN

Cigarette smoking and hyperfibrinogenaemia are both significant risk factors for the development of cardiovascular disease. Two studies are described here which aimed to establish the metabolic mechanism responsible for the raised plasma fibrinogen concentration observed in smokers. Chronic smokers had a significantly elevated absolute rate of fibrinogen synthesis (ASR) compared with non-smokers (22.7±1.3 mg/kg per day versus 16.0±1.3 mg/kg per day; means±S.E.M., P < 0.01), with plasma levels of fibrinogen significantly correlated with fibrinogen synthesis (r = 0.65, P = 0.04). Unlike fibrinogen, plasma albumin concentrations were lower in smokers than in non-smokers (45±0.4 versus 47±0.7 g/l, P < 0.05), but there was no difference in rates of albumin synthesis between the two groups. Two weeks cessation from smoking by previously chronic smokers was associated with a rapid and marked fall in plasma fibrinogen concentration (from 3.06±0.11 g/l to 2.49±0.14 g/l, P < 0.001), and a significant reduction in ASR (a 33% reduction, from 24.1±1.7 to 16.1±1.0 mg/kg per day, P < 0.001). These studies suggest a primary role for increased synthesis in producing the hyperfibrinogenaemia associated with smoking. Moreover, abstention from smoking for a period of only 2 weeks induces a significant decrease in the rate of fibrinogen synthesis by the liver, with a concomitant reduction in the plasma fibrinogen concentration.


Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1908 ◽  
Author(s):  
Cinzia Ingallina ◽  
Anatoly P. Sobolev ◽  
Simone Circi ◽  
Mattia Spano ◽  
Caterina Fraschetti ◽  
...  

The chemical composition of the inflorescences from four Cannabis sativa L. monoecious cultivars (Ferimon, Uso-31, Felina 32 and Fedora 17), recently introduced in the Lazio Region, was monitored over the season from June to September giving indications on their sensorial, pharmaceutical/nutraceutical proprieties. Both untargeted (NMR) and targeted (GC/MS, UHPLC, HPLC-PDA/FD and spectrophotometry) analyses were carried out to identify and quantify compounds of different classes (sugars, organic acids, amino acids, cannabinoids, terpenoids, phenols, tannins, flavonoids and biogenic amines). All cultivars in each harvesting period showed a THC content below the Italian legal limit, although in general THC content increased over the season. Citric acid, malic acid and glucose showed the highest content in the late flowering period, whereas the content of proline drastically decreased after June in all cultivars. Neophytadiene, nerolidol and chlorogenic acid were quantified only in Felina 32 cultivar, characterized also by a very high content of flavonoids, whereas alloaromadendrene and trans-cinnamic acid were detected only in Uso-31 cultivar. Naringenin and naringin were present only in Fedora 17 and Ferimon cultivars, respectively. Moreover, Ferimon had the highest concentration of biogenic amines, especially in July and August. Cadaverine was present in all cultivars but only in September. These results suggest that the chemical composition of Cannabis sativa L. inflorescences depends on the cultivar and on the harvesting period. Producers can use this information as a guide to obtain inflorescences with peculiar chemical characteristics according to the specific use.


1990 ◽  
Vol 40 (9) ◽  
pp. 2023-2028 ◽  
Author(s):  
Marisabel Mourelle ◽  
Denise Beales ◽  
Andre E.M. McLean

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