Linked Life Data

2276174

Source:http://linkedlifedata.com/resource/pubmed/id/2276174

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1991-3-4
pubmed:abstractText
Regulation by vitamin A of cell proliferation and differentiation of epithelial tissues is well-established. Deficiency of vitamin A in experimental animals leads to the development of hyperplasia and squamous metaplasia. The objective of the present study was to examine, for young hamsters, the effects of variable levels of the vitamin in the liver and trachea, on cell proliferation and morphology of tracheal epithelium and on body weights. Newly born litters were maintained on vitamin A-supplemented and vitamin A-deficient diets, and various parameters were examined at different ages. Retinol and retinyl palmitate levels were determined by high performance liquid chromatography. For animals on the supplemented diet, concentrations of liver retinyl palmitate and retinol increased progressively with age, reaching highest levels of approximately 84 and 1.9 micrograms g liver, respectively, at 28 d. In contrast, in animals on the vitamin A-deficient diet, the retinyl palmitate and retinol levels decreased progressively, reaching the lowest levels of approximately 0.32 and 0.09 micrograms/g, respectively. No significant reduction in retinol was observed in the trachea of animals maintained on the deficient diet for at least 20 d: their tracheas were depleted of retinol at 28 d. No vitamin A-associated differences were, however, observed in the labelling indices, growth fraction or in the morphology of the tracheal epithelium. Both the control and vitamin A-deficient animals gained weight progressively until 36 d of age, although the weight of animals in the latter group remained below those in the former group. These results show that mild-to-severe deficiency of vitamin A had no effects on cell proliferation or tracheal morphology of the hamster. The hyperplasia and squamous metaplasia in the trachea occurs only at an extreme vitamin A-deficiency when the tissue levels of the vitamin are depleted.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0008-8730
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
575-86
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Effects of vitamin A deficiency on cell proliferation and morphology of trachea of the hamster.
pubmed:affiliation
Wayne State University, Institute of Chemical Toxicology, Detroit, MI 48201.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.