Linked Life Data

932038

Source:http://linkedlifedata.com/resource/pubmed/id/932038

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
1976-9-2
pubmed:abstractText
Synthesis of heme and cytochrome P-450 have been studied in adult rat hepatocytes in primary monolayer culture. Incubation of cells with delta-aminolevulinic acid increases both cellular heme and cytochrome P-450 relative to that found in cells incubated under control conditions. Formation of heme is proportional to the concentration of delta-aminolevulinic acid in the culture medium and is not saturable. By contrast, formation of cytochrome P-450 is saturable; excess intracellular heme appears as a new absorption band at 420 nm in the carbon monoxide-reduced difference spectrum. We have studied the effect of cobalt on heme and hemoprotein formation in this cell system. The metal blocks formation of cytochrome P-450 but fails to affect heme synthesis. In contrast to previous findings with isolated mitochondria, no cobalt protoporphyrin formed in hepatocytes cultured in the presence of the metal. In studies of rats in vivo, it was confirmed that cobalt acts to reduce the amount of [14C]heme in the liver after administration of delta-amino[14C]levulinic acid. However, the present findings suggest that this effect of cobalt represents accelerated breakdown of newly labeled hepatic heme rather than inhibition of synthesis. We conclude that cobalt interferes with formation of cytochrome P-450 not by direct inhibition of heme synthesis but most likely by blocking the association of heme and apocytochrome.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
251
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4421-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Effect of cobalt on synthesis of heme and cytochrome P-450 in the liver. Studies of adult rat hepatocytes in primary monolayer culture and in vivo.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.