Linked Life Data

6771268

Source:http://linkedlifedata.com/resource/pubmed/id/6771268

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
1980-9-28
pubmed:abstractText
High levels of NaCN (20 to 250 mM) were required to inhibit cyclooxygenase catalysis and cause extended lag periods (up to 1.6 min), whereas CO failed to inhibit catalysis. This NaCN inhibition was easily overcome by endogenous or exogenous hydroperoxides. Added hydroperoxides acted to eliminate lag periods without undergoing net conversion to other chemical species. In addition, experiments with glutathione peroxidase inhibition showed that hydroperoxides were essential not only in the early phases, but throughout catalysis. In spectrophotometric experiments, NaCN formed a complex with ferriheme cyclooxygenase (Kd = 1.3 mM) and inhibited hydroperoxide interaction with this form of the enzyme. Phenolic antioxidants, only slightly extended lag periods while inhibiting oxygenation rates more than 50%. Low levels of phenol (which is normally stimulatory) or alpha-naphthol when combined with NaCN or glutathione peroxidase (agents which interfere with peroxide activation) resulted in potent synergistic inhibition with long lag times. A mechanism consistent with all of the above properties of cyclooxygenase has been elucidated, Further mechanistic explanation was sought for reaction-catalyzed self-inactivation of cyclooxygenase. This phenomenon could not be explained simply by heme lability, or cyclooxygenase sensitivity to destruction by ambient hydroperoxides, Rather, it appears to involve a destructive reaction intermediate intrinsic to involve a destructive reaction intermediate intrinsic to the cyclooxygenase mechanism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Arachidonic Acids, http://linkedlifedata.com/resource/pubmed/chemical/Carbon Monoxide, http://linkedlifedata.com/resource/pubmed/chemical/Cyclooxygenase Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Free Radicals, http://linkedlifedata.com/resource/pubmed/chemical/Glutathione Peroxidase, http://linkedlifedata.com/resource/pubmed/chemical/Heme, http://linkedlifedata.com/resource/pubmed/chemical/Naphthols, http://linkedlifedata.com/resource/pubmed/chemical/Peroxides, http://linkedlifedata.com/resource/pubmed/chemical/Phenols, http://linkedlifedata.com/resource/pubmed/chemical/Prostaglandin-Endoperoxide Synthases, http://linkedlifedata.com/resource/pubmed/chemical/Prostaglandins, http://linkedlifedata.com/resource/pubmed/chemical/Sodium Cyanide
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
255
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6253-61
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Evidence for a peroxide-initiated free radical mechanism of prostaglandin biosynthesis.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, Non-P.H.S.