Linked Life Data

8857667

Source:http://linkedlifedata.com/resource/pubmed/id/8857667

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-12-30
pubmed:abstractText
The proportions in which two eumelanin monomers, namely 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI), compose the eumelanin polymer are believed to determine properties of the pigment including its color. These proportions are, however, not well elucidated for naturally occurring eumelanins, largely because of methodological difficulties. In this study we estimate the content of DHICA-derived units in mammalian eumelanins using a combination of two analytical techniques: 1) quantitation of DHICA-derived eumelanin by measuring the yield of pyrrole-2,3,5-tricarboxylic acid (PTCA index) and 2) spectrophotometrical quantitation of total (DHI + DHICA) eumelanin at 350 nm (A350 index). The ratio of PTCA/A350 measured for melanins synthesized from DHI and DHICA mixed in various molar proportions correlates well with the content of DHICA in synthetic polymers. Using this relationship as a standard curve we estimated the proportion of DHICA-derived units in mammalian eumelanins from hair and melanoma cells and found it to be much higher in rodent pigments (58.8%-98.3%; two species, mouse and hamster were examined) as compared to human eumelanins (19.2%-41.8%; one Caucasian and one Oriental individual were examined). No relationship between proportion of DHICA-derived units in eumelanin and hair color is found. The latter seems to be determined predominantly by the ratio of pheo- to eumelanin synthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0893-5785
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
63-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Composition of mammalian eumelanins: analyses of DHICA-derived units in pigments from hair and melanoma cells.
pubmed:affiliation
Mishima Institute for Dermatological Research, Kobe, Japan.
pubmed:publicationType
Journal Article, Comparative Study