Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
13
|
pubmed:dateCreated |
1981-8-27
|
pubmed:abstractText |
Administration of 3,5-dicarbethoxy-1,4-dihydrocollidine (DDC) to rats causes the accumulation of N-methylprotoporphyrin IX, a potent inhibitor of ferrochelatase. To clarify the origin of the porphyrin N-methyl group, we have synthesized and administered to rats N-ethyl-3,5-dicarbethoxy-1,4-dihydrocollidine (N-ethyl DDC) and 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine (DDEP), the DDC analogue with a 4-ethyl rather than 4-methyl group. Only N-methylprotoporphyrin IX is isolated from rats treated with the former agent, and only N-ethylprotoporphyrin IX from those treated with the latter. All four isomers of N-ethylprotoporphyrin IX are formed biologically. The structure of the isolated porphyrins has been confirmed by complete spectroscopic comparison with the four synthetic isomers of N-ethylprotoporphyrin IX. DDEP has been shown to cause NADPH- and time-dependent in vitro loss of hepatic microsomal cytochrome P-450. These results unequivocally establish that the 4-alkyl groups in DDC and dDEP are the source of the N-alkyl group in N-methyl- and N-ethylprotoporphyrin IX, respectively, and strongly suggest that the alkyl group is transferred to the prosthetic heme of cytochrome P-450 during catalytic processing of the substrate by the enzyme. The mechanism of the group transfer is discussed.
|
pubmed:grant | |
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Cytochrome P-450 Enzyme System,
http://linkedlifedata.com/resource/pubmed/chemical/Dicarbethoxydihydrocollidine,
http://linkedlifedata.com/resource/pubmed/chemical/N-methylprotoporphyrin IX,
http://linkedlifedata.com/resource/pubmed/chemical/Porphyrins,
http://linkedlifedata.com/resource/pubmed/chemical/Protoporphyrins,
http://linkedlifedata.com/resource/pubmed/chemical/Pyridines
|
pubmed:status |
MEDLINE
|
pubmed:month |
Jul
|
pubmed:issn |
0021-9258
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
10
|
pubmed:volume |
256
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
6708-13
|
pubmed:dateRevised |
2007-11-14
|
pubmed:meshHeading |
pubmed-meshheading:6894597-Animals,
pubmed-meshheading:6894597-Chromatography, High Pressure Liquid,
pubmed-meshheading:6894597-Cytochrome P-450 Enzyme System,
pubmed-meshheading:6894597-Dicarbethoxydihydrocollidine,
pubmed-meshheading:6894597-Magnetic Resonance Spectroscopy,
pubmed-meshheading:6894597-Male,
pubmed-meshheading:6894597-Microsomes, Liver,
pubmed-meshheading:6894597-Porphyrins,
pubmed-meshheading:6894597-Protoporphyrins,
pubmed-meshheading:6894597-Pyridines,
pubmed-meshheading:6894597-Rats,
pubmed-meshheading:6894597-Structure-Activity Relationship
|
pubmed:year |
1981
|
pubmed:articleTitle |
N-Alkylprotoporphyrin IX formation in 3,5-dicarbethoxy-1,4-dihydrocollidine-treated rats. Transfer of the alkyl group from the substrate to the porphyrin.
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
|