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ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2)
The distribution of vitamins A(1) and A(2) has been determined in the eye tissues and livers of a number of fishes. The vitamins were differentiated by means of the antimony chloride reaction, which yields with A(1) a band at 615–620 mµ and with A(2) a band at about 696 mµ. In the retina the presenc...
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Formato: | Texto |
Lenguaje: | English |
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The Rockefeller University Press
1939
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2142001/ https://www.ncbi.nlm.nih.gov/pubmed/19873110 |
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author | Wald, George |
author_facet | Wald, George |
author_sort | Wald, George |
collection | PubMed |
description | The distribution of vitamins A(1) and A(2) has been determined in the eye tissues and livers of a number of fishes. The vitamins were differentiated by means of the antimony chloride reaction, which yields with A(1) a band at 615–620 mµ and with A(2) a band at about 696 mµ. In the retina the presence of vitamin A(1) is diagnostic of the operation of a rhodopsin, and vitamin A(2) of a porphyropsin cycle. The eye tissues of all permanently marine fishes examined, except the tautog, contain vitamin A(1) alone. Those of all permanently freshwater fishes possess only vitamin A(2). Those of all euryhaline (potentially migratory) fishes, except possibly the alewife, contain mixtures of both vitamins A, and always predominantly that one which ordinarily is associated with the environment in which the fish is spawned. These correlations extend in part to the liver oils, but most livers contain mixtures of both vitamins A, and occasionally in proportions the reverse of those in the eye tissues. The vitamin A configuration does not depend upon environmental circumstances, but is determined genetically. The transfer from vitamin A(1) to A(2) metabolism appears associated phylogenetically with migration of marine teleosts into fresh water. |
format | Text |
id | pubmed-2142001 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1939 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21420012008-04-23 ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2) Wald, George J Gen Physiol Article The distribution of vitamins A(1) and A(2) has been determined in the eye tissues and livers of a number of fishes. The vitamins were differentiated by means of the antimony chloride reaction, which yields with A(1) a band at 615–620 mµ and with A(2) a band at about 696 mµ. In the retina the presence of vitamin A(1) is diagnostic of the operation of a rhodopsin, and vitamin A(2) of a porphyropsin cycle. The eye tissues of all permanently marine fishes examined, except the tautog, contain vitamin A(1) alone. Those of all permanently freshwater fishes possess only vitamin A(2). Those of all euryhaline (potentially migratory) fishes, except possibly the alewife, contain mixtures of both vitamins A, and always predominantly that one which ordinarily is associated with the environment in which the fish is spawned. These correlations extend in part to the liver oils, but most livers contain mixtures of both vitamins A, and occasionally in proportions the reverse of those in the eye tissues. The vitamin A configuration does not depend upon environmental circumstances, but is determined genetically. The transfer from vitamin A(1) to A(2) metabolism appears associated phylogenetically with migration of marine teleosts into fresh water. The Rockefeller University Press 1939-01-20 /pmc/articles/PMC2142001/ /pubmed/19873110 Text en Copyright © Copyright, 1939, by The Rockefeller Institute for Medical Research This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Article Wald, George ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2) |
title | ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2)
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title_full | ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2)
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title_fullStr | ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2)
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title_full_unstemmed | ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2)
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title_short | ON THE DISTRIBUTION OF VITAMINS A(1) AND A(2)
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title_sort | on the distribution of vitamins a(1) and a(2) |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2142001/ https://www.ncbi.nlm.nih.gov/pubmed/19873110 |
work_keys_str_mv | AT waldgeorge onthedistributionofvitaminsa1anda2 |