Linked Life Data

9570325

Source:http://linkedlifedata.com/resource/pubmed/id/9570325

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1998-5-13
pubmed:abstractText
The formation of zinc protoporphyrin in response to lead or iron depletion has previously been investigated in erythroid systems. Because of its possible metabolic role in non-erythroid tissue, we investigated the formation of zinc protoporphyrin in cultured hepatocytes. The effects of lead and inhibitors of ferrochelatase, the iron insertion step of heme synthesis, on the conversion of 5-aminolevulinic acid to zinc protoporphyrin, protoporphyrin and heme were compared in rat and chick embryo hepatocyte cultures. In rat cultures, zinc protoporphyrin was synthesized enzymatically by ferrochelatase, since N-methylmesoporphyrin, an inhibitor of ferrochelatase. caused 40% or greater decreases in both heme and zinc protoporphyrin accumulation and markedly stimulated protoporphyrin accumulation. In addition, chelation of ferrous iron with 2,2'-dipyridyl decreased heme accumulation by 50%, but increased ZPP accumulation by 200%. Zinc protoporphyrin formation in chick embryo hepatocytes required the addition of zinc as well as 5-aminolevulinic acid and apparently was non-enzymatic, since it was not inhibited by N-methylmesoporphyrin nor increased by iron chelation. In the presence of 5-aminolevulinic acid, lead had no effect on zinc protoporphyrin, protoporphyrin or heme accumulation in chick hepatocytes, but decreased all three in rat hepatocytes, with the decrease in protoporphyrin being far greater than that of zinc protoporphyrin or heme. These findings indicate that, in contrast to the effect of lead in erythroid tissue, it did not specifically increase zinc protoporphyrin accumulation or alter iron availability in cultured hepatocytes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0300-483X
pubmed:author
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
125
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
95-105
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Formation of zinc protoporphyrin in cultured hepatocytes: effects of ferrochelatase inhibition, iron chelation or lead.
pubmed:affiliation
Department of Microbiology, Dartmouth Medical School, Hanover, NH 03755, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.