Linked Life Data

3006731

Source:http://linkedlifedata.com/resource/pubmed/id/3006731

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1986-5-1
pubmed:abstractText
Inorganic pyrophosphate (PPi) and two diphosphonates, ethane-1-hydroxy-1, 1-diphosphonate (EHDP) and dichloromethylene diphosphonate (Cl2MDP), were found to inhibit in vitro mineralization induced by matrix vesicle-enriched fractions from chicken epiphyseal cartilage. Inhibitor concentrations from 0.20 to 20 microM caused a dosage-dependent decrease in 45Ca and 32Pi uptake by the vesicle fraction. These inhibitors were also tested in a hydroxyapatite (HA)-seeded system to help distinguish between effects on the mineral vs nonmineral portions of the vesicle fraction. The order of inhibition of the HA-seeded system was EHDP greater than PPi greater than Cl2MDP, except for inhibitor concentrations of 0.20 microM where EHDP was the least inhibitory. This variation may be due to differences in the binding of the inhibitors to HA crystals. In general, inhibition of HA mineralization was greatest during later time periods, whereas vesicle ion uptake was affected more during early stages of incubation. The differential effects of the three inhibitors were most obvious at the 2.0 microM concentration. With PPi substantial inhibition of HA-seeded mineralization was observed even in late stages of the study; in contrast, with time the vesicle fraction overcame this inhibition. This suggests that alkaline phosphatase, an enzyme notably enriched in matrix vesicles, catalyzed the hydrolysis of PPi, reducing its concentration to a level where mineralization could proceed. Our findings show that matrix vesicle-induced mineralization differs significantly from apatite-induced mineralization. The data support the concept that vesicle alkaline phosphatase acts, at least in part, to remove physiological crystal growth inhibitors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
8756-3282
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
307-12
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Effect of pyrophosphate and two diphosphonates on 45Ca and 32Pi uptake and mineralization by matrix vesicle-enriched fractions and by hydroxyapatite.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't