Linked Life Data

8457547

Source:http://linkedlifedata.com/resource/pubmed/id/8457547

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1993-4-23
pubmed:abstractText
The osteoclast proton pump (OC H(+)-ATPase) differs from other vacuolar H(+)-ATPases (V-ATPases) in its sensitivity to vanadate and in the subunit composition of its catalytic domain, where isoforms of subunits A and B are expressed [Chatterjee et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 6257-6261]. In the present study, the sensitivity of the osteoclast H(+)-ATPase to various oxyanions was tested. The results indicate that H+ transport by microsomal preparations isolated from chicken osteoclasts is 20-100-fold more sensitive to nitrate that any other animal and fungal V-ATPases and 10-20-fold more sensitive than plant V-ATPases, as is the ATPase activity of the affinity-purified enzyme. This inhibition by nitrate is not due to a chaotropic effect of the oxyanion and is complete at 1 mM concentrations with an IC50 of 100 microM. In contrast, proton transport by the OC H(+)-ATPase was insensitive to other oxyanions (phosphate, sulfate, and acetate) which inhibit other V-ATPases. These results further demonstrate that the proton pump present in osteoclast membranes differs from other vacuolar ATPases. It is speculated that, since cells of the macrophage lineage can generate high intracellular concentrations of nitrate, it may be possible to physiologically or therapeutically regulate the activity of the OC H(+)-ATPase in the osteoclast without affecting the other V-ATPases in the same or in other cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2808-12
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Sensitivity to nitrate and other oxyanions further distinguishes the vanadate-sensitive osteoclast proton pump from other vacuolar H(+)-ATPases.
pubmed:affiliation
Department of Orthopedics, Yale University School of Medicine, New Haven, Connecticut 06510.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't