Vitamin A

Moore, T

doi:10.1136/pgmj.17.185.52

Cited by 16 publications

(23 citation statements)

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“…Retinol (vitamin A) in lung was demonstrated over 50 years (15) ago, but the exact function of this nutrient in pulmonary metabolism and its potential relationship to neonatal lung development is only of recent interest.…”

Section: Hplc High Performance Liquid Chromatographymentioning

confidence: 99%

Perinatal Rat Lung Retinol (Vitamin A) and Retinyl Palmitate

1984

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ABSTRAm. The potential role for retinol (vitamin A alcohol) in the differentiation of the developing lung prompted this study in the perinatal rat. High performance liquid chromatography was used to separate, detect, and quantitate retinol and retinyl palmitate in lipid extracts of tissue and serum. Fetal and maternal blood showed the presence of retinol, whereas no retinyl palmitate was detected. On the other hand, fetal and postnatal lungs contained retinyl palmitate as well as retinol. Considerable changes in the content of lung retinyl palmitate were found during lung development. Retinol is essential for differentiation and integrity of respiratory epithelial cells of upper airways (1, 25). Lung cytosol contains intracellular retinol and retinoic acid-binding proteins (17,18); the quantity of the latter changes postnatally in the rat (17). Since one-fourth of the cells in the alveolar region of lung are epithelial (6), clinical studies on neonatal retinol status (3, 13, 19,2 1) and retinal's possible relationship to neonatal lung disease (10, 20) are being assessed.The ability of rat lung to accumulate retinol after large doses (15) poses questions concerning the existence of a lung storage form of vitamin A, its chemical character, and function. Adult rat lungs contained retinyl esters after intravenous injections of chylomicra labeled with radioactive retinyl esters. The major ester was retinyl palmitate (9). Recently, HPLC identified retinyl palmitate and smaller amounts of other retinyl esters in adult rat lung (2). Although it is well established that retinyl esters (mainly The objective here was to study whether fetal lungs contain retinyl palmitate and to determine whether the amounts of retinol and retinyl palmitate change during perinatal develop ment of rat lung. High performance liquid chromatography. Retinol and retinyl palmitate were determined by HPLC using a programmable liquid chromatographic system (Spectra Physics; San Jose, CA). The UV spectrophotometer system was a ISCO-V4 variable detector (Lincoln, NE). The HPLC column was reversed-phase pBondapak CIO (10-pm particle size) stainless steel column, 3.9 mm i.d. x 30 cm (Waters Associates, Inc., Milford, MA). A modification of the system previously described was used (2). In our system, 100% methanol was used as the mobile phase to separate retinol, retinol acetate (added to some extracts as an internal standard), and retinyl palmitate. The flow rate was adjusted so retinol was eluted in the 5th min and retinyl palmitate in the 1 lth min. The flow rates were as follows: 0-5 min, 1.0 ml/min; 6 min, 1.5 ml/min; 7 min, 2.0 ml/min; 12 min, 1.5 ml/min; and 13 min, back to 1.0 ml/min. MATERIALS AND METHODS Chemicals. High p&ty spectral grade solvents of Burdick andStandard curves of peak heights at identical sensitivities of the instrument against known amounts of retinol and retinyl palmitate were used. The standard solutions of retinol and retinyl palmitate were prepared in 100% ethanol and quantitated using the extinction coefficient of E!Fm...

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Section: Hplc High Performance Liquid Chromatographymentioning

confidence: 99%

Perinatal Rat Lung Retinol (Vitamin A) and Retinyl Palmitate

1984

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“…These concentrations are lower, and that in the kidney much lower, than those hitherto reported in hyperthyroid goats from this laboratory (Chanda & Owen, 1952). The known antithyroid action of vitamin A and carotene in a number of species (see books and reviews of Lindquist, 1938;Brody, 1945;Moore, 1957;Goodwin, 1952;Owen, 1941Owen, , 1947Owen, , 1951Owen, , 1954) and the anti-metabolic effect of vitamin A (Leutskii, I 961) make it reasonable to attribute the effect of carotene deprivation on the heart rate of the goat to the damping of the thyroid by dietary carotene. T h e interaction of the thyroid and vitamin A is complex (Chanda & Owen, 1952;Owen, 1962;Chanda, Clapham & Owen, 1955;Paul, Chanda & Chakraborty, 1962) and may be evident only when the intake of carotene is either too great or too small (Frape, Speer, Hayes & Catron, 1959).…”

Section: Abstracts Of Communications I963mentioning

confidence: 50%

Abstracts of Communications

1963

Proc. Nutr. Soc.

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“…Feeding with a diet containing 900 pg retinol/kg caused increases in both liver and plasma vitamin A. According to Moore (1957), there is in rats an efficient mechanism which keeps the plasma vitamin A concentration constant independently of its content in liver or diet. It seems that in chicks such a control mechanism is much less efficient.…”

Section: Vitamin a De$ciency And Protein Catabolism 9 D I S C U S S Imentioning

confidence: 99%

Effect of vitamin A deficiency on protein catabolism in chicks

1974

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1. The changes in the concentration of some enzymes and their metabolites were studied in the first stages of vitamin A deficiency in chicks.2. Kidney arginase (EC3.5.3.1) and liver xanthine dehydrogenase activities had increased even before complete disappearance of vitamin A from the plasma. Similarly, an increase was found in plasma uric acid, and plasma urea also increased but to a lesser extent. Liver proteolytic activity also was slightly increased by vitamin A deficiency.3. Kidney D-amino acid oxidase (EC1.4.3.3) activity and plasma concentrations of total protein and free amino acids were not affected, at least in the first stages of the deficiency.4. Oral dosing of deficient chicks with retinyl palmitate to provide 300 μg retinol, 24 h before killing, brought about a decrease in the activities of both enzymes and of plasma uric acid, and an increase in plasma urea.5. Dietary levels of vitamin A were reflected not only in the liver concentrations of the vitamin but also in the plasma concentrations.

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Vitamin A

Cited by 16 publications

References 0 publications

Perinatal Rat Lung Retinol (Vitamin A) and Retinyl Palmitate

Perinatal Rat Lung Retinol (Vitamin A) and Retinyl Palmitate

Abstracts of Communications

Effect of vitamin A deficiency on protein catabolism in chicks

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