Metabolism of Nucleic Acids and Protein in the Liver, Brain, and Kidney of Female Rats Subjected to Dietary Restriction During the Period of Gestation as well as the Period of Growth, Gestation, and Lactation

1972 ◽  
Vol 50 (8) ◽  
pp. 832-839 ◽  
Author(s):  
Uma Srivastava ◽  
My-Lien Vu ◽  
Suraj Bhargava ◽  
Tapas Goswami

The metabolism of nucleic acids and protein, and. cellular growth, were studied in various organs of female rats subjected to a diet restriction during the period of gestation as well as the period of growth, gestation, and lactation. In general, both body and organ growth were retarded during this restriction, with certain exceptions. For example, only the liver demonstrated a decrease in organ weight when the diet was restricted during the period of gestation only. The number of cells in the various organs decreased in the experimental groups, whereas the cell size was observed to increase. Furthermore it was found that restrictions during the period of growth, gestation, and lactation increased the accumulation of cellular ribonucleic acid and protein content. The metabolism of ribonucleic acid and protein also seemed to have increased significantly.It was concluded that although dietary restriction caused changes in cellular growth, size, and metabolism of various organs these changes were much less marked when the restriction was imposed only during the period of gestation.

1953 ◽  
Vol 9 (1) ◽  
pp. 52-67 ◽  
Author(s):  
ROSA M. CAMPBELL ◽  
I. R. INNES ◽  
H. W. KOSTERLITZ

1. Excess ribonucleic acid ('RNA') is defined as the difference between the RNA contents of livers of pregnant and non-pregnant rats. Large amounts of excess RNA are formed in the liver of the rat during the last week of pregnancy. Excess RNA is formed in the liver after removal, on the 14th or 15th day of pregnancy, of the foetuses, or foetuses and ovaries, or foetuses and adrenals, or foetuses, ovaries and adrenals, or pituitary, or pituitary and foetuses, or pituitary, foetuses and ovaries. Viable placentae must be present. 2. Two fractions of RNA appear to be present in the liver cells of pregnant rats. One fraction varies linearly with the protein content of the liver cells, as does the RNA of non-pregnant rats' livers. The second fraction (excess RNA) is quite independent of the protein content of the liver cells but varies linearly with the weight of the placentae and the energy, but not the protein, content of the diet. 3. Hypophysectomy lowers the amount of excess RNA by 20–25 %. After removal of the foetuses on the 14th day, the placentae do not attain the normal weight, and the amount of excess RNA is smaller than in normal pregnancy. After removal of foetuses and ovaries the placentae are larger and heavier than after removal of the foetuses alone. 4. Both adrenalectomy and ovariectomy in non-pregnant female rats cause a small rise of liver deoxyribonucleic acid ('DNA') and RNA. After hypophysectomy, there is a loss in liver RNA greater than that expected from the simultaneous loss of liver protein. The loss of RNA occurs even when the loss of liver protein is prevented by feeding the rats by stomach tube. DNA is not lost from the liver a fortnight after hypophysectomy, as long as the energy intake is normal. 5. In non-pregnant female rats oestradiol, but not progesterone, causes an increase of liver DNA and RNA. This is not found in hypophysectomized rats. Injection of an alkaline placental extract causes a significant rise of liver RNA which, however, is very much smaller than that found in pregnancy. 6. Since hypophysectomy lowers, but does not abolish excess liver RNA in pregnant rats, it is concluded that at least two factors play a role: first and foremost, an unknown factor secreted by the placenta, acting independently of the pituitary, and second, increased amounts of oestrogen apparently requiring the presence of the pituitary.


Author(s):  
A B McAllan ◽  
G D Braithwaite

Little attention has been directed at defining the ‘protein’ fraction of silages. This component is normally estimated by fractionation based on solubility characteristics and under the conditions most commonly used, nucleic acids (ribonucleic acid (RNA) and deoxyribonucleic acid (DNA)) would appear in the protein fraction. Grasses and legumes can contain appreciable amounts of nucleic acids ranging from 11-29 and 19-53 g/kg dry matter respectively (McAllan, 1982). No information is available as to the effects of ensilage on these nucleic acids. Microbes also contain appreciable amounts of nucleic acids which can account for 150-200 gN/kg total-N of the cell and these amounts may vary according to the stage of growth. It has been suggested (Ullrich, 1982) that microbial-N contribution to the total-N content of silage is as much as 220-280 g/kg. Thus the total amount of silage ‘protein-N’ present in the form of nucleic acid-N (from both plant and microbes) could be appreciable leading to a considerable overestimation of the ‘protein’ content of the silage.


1978 ◽  
Vol 56 (2) ◽  
pp. 274-286 ◽  
Author(s):  
Tapas Goswami ◽  
Uma Srivastava

The effect of maternal dietary deficiency on the metabolism of nucleic acids and proteins was studied by exchanging the pups of control and undernourished dams during the lactation period. In the pups of control dams fostered by undernourished dams during the lactation period (E3), it was observed that the body and organ weight, and RNA, DNA, and protein content failed to increase normally. Contrary to this, the free leucine and nucleotide contents were higher and their specific activities lower in the plasma and various organs of the E3 group as compared with the control group.Specific activity of protein was higher in the liver, brain, kidney, and lung, and was lower in the spleen and heart of the E3 group as compared with the control group. Specific activity of RNA was higher in the liver, spleen, and lung, and was lower in the brain, kidney, and heart of the E3 group as compared with the control group.In the pups of undernourished dams fostered by the control dams during the lactation period (E1), the body and organ weights, the RNA, DNA, and protein content, the content of free leucine and nucleotides as well as their specific activities, and the specific activity of protein and RNA were partially or completely restored. However, the DNA content of the brain remained unchanged in comparison with those pups of undernourished dams nursed by their own mother (E2). In the brain, kidney, spleen, and lung of the E1 group, the specific activity of RNA increased considerably and even exceeded the control values.The radioactivity results discussed above clearly demonstrate an accelerated metabolism of protein and RNA in the various organs of the E3 group and a partial or complete normalization in the E1 group.


2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Ruping Fan ◽  
Lisa M. Schrott ◽  
Stephen Snelling ◽  
John Felty ◽  
Derrel Graham ◽  
...  

1954 ◽  
Vol 38 (2) ◽  
pp. 145-148 ◽  
Author(s):  
A. D. Hershey

In experiments of 6 hours duration, no replacement of phosphorus or purine and pyrimidine carbon in DNA, nor flow of these atoms from RNA to DNA, could be detected in rapidly growing cultures of E. coli. The slow replacement that has been demonstrated for many substances in non-proliferating tissues of other organisms, though it may occur also in bacteria, is not greatly accelerated under conditions of rapid cellular growth, and therefore cannot be a characteristic feature of synthetic processes.


2003 ◽  
Vol 28 (7) ◽  
pp. 1257-1263 ◽  
Author(s):  
Rachel F Genn ◽  
Sonia Tucci ◽  
Jessica E Edwards ◽  
Sandra E File

1953 ◽  
Vol 9 (1) ◽  
pp. 45-51 ◽  
Author(s):  
ROSA M. CAMPBELL ◽  
H. W. KOSTERLITZ

1. The protein content of liver cells is almost independent of the size of the animal (mice, cats and previous results on rats, Campbell & Kosterlitz [1949]), and varies with the amount of protein eaten. 2. As has already been shown for rats, the ribonucleic acid ('RNA') content of the liver cells of non-pregnant mice, guinea-pigs and cats varies directly with the protein content of the cells. For a given protein content the mouse and rat have more RNA than the guinea-pig and cat. 3. During pregnancy there is a rise of the deoxyribonucleic acid ('DNA') content of the livers and in the protein content of the liver cells of mice (and rats), but not of guinea-pigs. 4. An excess of RNA over that predicted from the protein content of the liver cell has previously been found for the rat during pregnancy, and ascribed to the action of a placental factor on the maternal liver. A similar excess of RNA has now been observed in the mouse and, to a less extent, in the guinea-pig. It appears to be absent in the cat. 5. Possible causes of some of these species differences are considered.


Author(s):  
Muhammad Ahmed ◽  
Aisha Azmat

Objective: Somina (herbal medicine) is used in Pakistan as Unani anxiolytics. It is composed of five medicinal plants. The current work was designed to evaluate the general reproductive and teratogenic effects of somina in two consecutive generations of rats according to the OECD guideline.Methods: Fertility study (a two-phase study) was done in Sprague-Dawley rats. 1st part: three groups’ female rats (10 rats each group) received different doses orally. First group: The control group (saline), a single oral human dose of somina (2nd group: 285 mg/kg/day) and the high dose of somina (3rd group: 1g/kg/day) during the whole period of gestation till the delivery of pups named as F1 Breed. For the second part of study ten females were selected from each F1 breed (control, somina 285 mg/kg/d, somina 1g/kg/day) and administered the same treatment from day first of mating than the entire period of gestation until F1 breed delivered pups (F2 breed). For F1 and F2 breed the fertility index and litter size were determined. Some of the female rats (F1 and F2) were anesthetized and autopsied. The blood sample was subjected to biochemical analysis and serum liver function test: bilirubin, gamma-glutamyl transferase (γGT), alanine aminotransferase (ALT: SGPT), aspartate aminotransferase (AST: SGOT) and alkaline phosphatase (ALP) were measured spectrophotometrically. The uterine growth index, fertility index, and litter size were also measured to evaluate the teratogenic effects of somina treated rats.Results: The data showed that any significant different (P>0.05) was not found during the maternal examination (uterine growth index, fertility index) and reproductive parameters (litter size, the quantity of fetus, aborted or absorbed fetus) in somina treated rats as compare to control rats (P>0.05). Control and treated Pups did not show any significant (P>0.05) malformation and any congenital defects. Non-significant (P>0.05) changes were observed in liver function test. It was found normal in all groups. Macroscopic autopsy examination also did not reveal any significant (P>0.05) pathological findings in the liver, kidneys, and uterus.Conclusion: The oral administration of somina during the gestational period of pregnant female rats was not teratogenic/fetotoxic. Any adverse or deleterious effects were not observed at the dose of 285 mg/kg (human dose) or 1g/kg (3times greater than the human dose) during pregnancy, and it is safe in rats.


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