Linked Life Data

6123537

Source:http://linkedlifedata.com/resource/pubmed/id/6123537

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1982-8-26
pubmed:abstractText
Gamma-glutamyl transpeptidase (GGT), an enzyme of the gamma-glutamyl cycle, was demonstrated in 3 of 6 cell lines derived from a single B16 murine melanoma. Its activity in these cells varied a great deal, appeared to be correlated with the developmental cycle of the cells, and was greatest in young, actively melanogenic cells. Generally, the activity seemed parallel to that of tyrosinase, an enzyme specific for melanin synthesis. The levels of both enzymes tended to decline with prolonged in vitro cultivation, but could be readily renewed after one animal passage. The 3 cell lines that were GGT-negative were nonpigmented and DOPA-negative; so was a nonmelanogenic and nonmelanocytic rhesus cell line. Melanocyte-stimulating hormone (MSH) and theophylline both enhanced pigmentation in murine melanoma cells. The mechanisms of their action apparently differed. We found that theophylline increased both DOPA- and GGT- reactive cells, whereas MSH only increased DOPA-reactive cells. All 3 GGT-positive lines were tumorigenic, and 2 GGT-negative line were not tumorigenic. Our observations suggest that GGT plays a role in the melanin biosynthetic pathway and the its activity is greater in melanoma cells that are tumorigenic.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-202X
pubmed:author
pubmed:issnType
Print
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
57-62
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Theophylline and melanocyte-stimulating hormone effects on gamma-glutamyl transpeptidase and DOPA reactions in cultured melanoma cells.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't