scholarly journals On the storage of Ascorbic Acid in the organs of guinea pigs given crystalline Ascorbic Acid with a vitamin C-free diet1

1935 ◽  
Vol 72 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Erik Jacobsen
Keyword(s):  
1991 ◽  
Vol 260 (1) ◽  
pp. G108-G118 ◽  
Author(s):  
W. H. Karasov ◽  
B. W. Darken ◽  
M. C. Bottum

We measured ascorbic acid (AA) uptake across the intestinal brush border in vitro in intact tissue from guinea pigs fed maintenance AA (200 mg/kg diet) or made hypervitaminotic (5,000 mg/kg diet) or hypovitaminotic (chronically and acutely). Total uptake per centimeter ileum was 25-50% lower in hypervitaminotic juvenile, adult male, and lactating guinea pigs compared with their respective controls, whereas carrier-mediated D-glucose uptake and Na(+)-independent AA uptake were similar. High dietary ascorbate specifically reduced the Vmax for carrier-mediated AA uptake. Hypovitaminosis had no significant effect on uptake of AA or other solutes. We performed diet-switching experiments (high-AA diet to maintenance diet) with young and adult guinea pigs to determine the reversibility of the downregulation. In adult guinea pigs, the downregulation of AA uptake was reversible within 7 days. In the young of mothers fed high AA during pregnancy and lactation, and which fed on high AA for 14 days after weaning, the downregulation was reversible within 14 days. Thus regulation of AA uptake is reversible and therefore probably does not play a significant role in the development of vitamin C dependency in human adults, or their young, after ingestion of megadoses of ascorbic acid.


1995 ◽  
Vol 41 (1) ◽  
pp. 17-24 ◽  
Author(s):  
Emiko SUZUKI ◽  
Tadao KURATA ◽  
Mamoru TOMITA ◽  
Nobuhiko ARAKAWA

1967 ◽  
Vol 45 (6) ◽  
pp. 749-756 ◽  
Author(s):  
W. E. J. Phillips

The effect of administration of ascorbic acid to normal or vitamin A-deficient rats was studied in relation to hepatic levels of ubiquinones and sterols. Similar studies were made on tissues from guinea pigs deficient in vitamin C, vitamin A, or both. Vitamin A deficiency increased the concentration of liver ubiquinones in the rat. Administration of ascorbate did not influence tissue levels of ubiquinones or sterols. Vitamin C deficiency increased the concentration of sterols but not of ubiquinones in the liver of the guinea pig. Vitamin A deficiency did not increase ubiquinones nor did a combined deficiency of vitamins A and C. A secondary effect of vitamin C deficiency in the vitamin A-deficient rat is not the cause of increased ubiquinone levels.


1990 ◽  
Vol 13 (11) ◽  
pp. 688-695 ◽  
Author(s):  
Itaru YAMAMOTO ◽  
Sadaharu SUGA ◽  
Yoshihiro MITOH ◽  
Mari TANAKA ◽  
Norio MUTO
Keyword(s):  

1950 ◽  
Vol 28e (6) ◽  
pp. 262-270 ◽  
Author(s):  
Christine E. Rice ◽  
Paul Boulanger

Groups of guinea pigs on a basic diet of commercial rabbit pellets supplemented by fresh green grass or stored roots exhibited marked differences in the ascorbic acid level of their plasma. These differences were not accompanied by any significant variation either in the complement titer of the serum or the prothrombin time of the plasma. Such minor variations as were observed in these two activities did not parallel each other.


1945 ◽  
Vol 23e (1) ◽  
pp. 1-4
Author(s):  
J. Tuba ◽  
M. M. Cantor ◽  
G. Hunter

Rose hips, as a dry powder to ensure uniformity of sampling, have been assayed for vitamin C, guinea pigs being used as the test animal. It is here proved by the curative growth method of Harris and Olliver and by the serum phosphatase method of Gould and Schwachman, that the values given for ascorbic acid by titration with 2, 6-dichlorophenolindophenol in rose hips are substantially correct.


1960 ◽  
Vol 199 (3) ◽  
pp. 423-428 ◽  
Author(s):  
Susanne von Schuching ◽  
Theodore Enns ◽  
Arthur F. Abt

Tissues of scorbutic guinea pigs take up a greater percentage of radioactive ascorbic acid following a single injection than do the tissues of guinea pigs on higher vitamin C diets. After wounding, the scar tissue area contains a larger amount of ascorbic acid than distant tissue. Studies of total excretion following a single injection of l-ascorbic-i-C14 acid were conducted at three dietary intake levels, both before and after wounding. Results obtained show that the greatest differences from the preoperative C14 excretion occur during the immediate postoperative period, and after 36 hours the rate constants approximate. Relative to wounding, the guinea pigs on the three different dietary levels react with the same basic pattern; increased deposition of l-ascorbic-i-C14 acid in the scar tissue accompanied by less excretion of C14O2 and a slight increase in C14 activity in the urine. A simplified method for measurement of C14O2 is described. An explanation of human vitamin C requirement and a possible simple assay of ascorbic acid analogues are also suggested.


1981 ◽  
Vol 2 (2) ◽  
pp. 69-79
Author(s):  
D. Liakakos ◽  
P. Vlachos ◽  
N.L. Doulas ◽  
B. Litsios ◽  
D. Alexiou

1947 ◽  
Vol 45 (1) ◽  
pp. 70-87 ◽  
Author(s):  
H. M. Bruce ◽  
A. S. Parkes

1. A dry pelleted diet is described which, supplemented with fresh greenstuff, dried cabbage, or ascorbic acid, is highly satisfactory for the growth and maintenance of guinea-pigs.2. No evidence could be found that the pelleted diet alone was deficient in any other factor than vitamin C required by guinea-pigs, fresh greens and dehydrated cabbage being effective because of their high content of this vitamin.3. Vitamin C added to the diet as crystalline ascorbic acid or as present in dried lucerne meal is mostly destroyed by the pelleting process and is further reduced during storage.4. The aim of evolving a dry pelleted stable diet completely adequate for guinea-pigs has not yet been realized.It is a pleasure to acknowledge our indebtedness to Miss M. Olliver, Messrs Chivers & Sons Ltd., who carried out the ascorbic acid determinations and gave us much valuable advice.Our thanks are also due to Roche Products, who gave us the ascorbic acid, to the Director of Messrs Chivers & Sons Ltd. for the generous gift of 1 cwt. of standard dehydrated cabbage, to the Dehydration Division of the Ministry of Food for supplying two samples of sub-standard dehydrated cabbage, and to Mr D. G. Short, senior technician in charge of the animals at the Institute, who prepared the small-scale diets.


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