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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
|
| pubmed:dateCreated |
1976-6-2
|
| pubmed:abstractText |
Cell culture experiments using haematoporphyrin photosensitized bovine hoof fibroblasts and long-wave uv-irradiation revealed two distinct and separable patterns of lethal photosensitization according to two different sensitization procedures: (1) Photosensitization of cell membranes by short exposure (5 min) of cells to haematoporphyrin. (2) Cytoplasmic photosensitization elicited by a 2 h exposure of cells to haematoporphyrin. Cell membrane photosensitization was reversible by incubation of cells in serum which removed surface bound haematoporphyrin; cytoplasmic photosensitization was irreversible. Beta-carotene was tested in these two systems and the following results were obtained: (1) Preincubation of bovine hoof fibroblasts in beta-carotene protects from lethal haematoporphyrin photosensitization. (2) Protection with beta-carotene is achieved against both types of photosensitization. (3) The protective effect of beta-carotene depends upon the duration of pretreatment, reaching a maximum after 7 days. (4) Beta-carotene protection is maintained even after trypsinization of bovine hoof fibroblasts and withdrawal of beta-carotene from the medium for 24 h or more. (5) Haematoporphyrin sensitized bovine hoof fibroblasts show a distinct pattern of red fluorescence for each type of photosensitization. Incubation of bovine hoof fibroblasts in beta-carotene prior to haematoporphyrin photosensitization results in a pronounced reduction of red fluorescence. Some of these data indicate that beta-carotene acts, at least in cell membrane photosensitization, at the level of the cell membrane into which it appears to be incorporated.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Mar
|
| pubmed:issn |
0007-0963
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
94
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
263-271
|
| pubmed:dateRevised |
2003-11-14
|
| pubmed:meshHeading |
pubmed-meshheading:943170-Animals,
pubmed-meshheading:943170-Carotenoids,
pubmed-meshheading:943170-Cattle,
pubmed-meshheading:943170-Cell Membrane,
pubmed-meshheading:943170-Cells, Cultured,
pubmed-meshheading:943170-Fibroblasts,
pubmed-meshheading:943170-Hematoporphyrins,
pubmed-meshheading:943170-Photosensitivity Disorders,
pubmed-meshheading:943170-Radiation Effects,
pubmed-meshheading:943170-Ultraviolet Rays
|
| pubmed:year |
1976
|
| pubmed:articleTitle |
Protective action of beta-carotene against lethal photosensitization of fibroblasts in vitro.
|
| pubmed:publicationType |
Journal Article
|