| A facilitative role for carbonic anhydrase activity in matrix vesicle mineralization. | |
| | |
MedLine Citation:
|
PMID: 7950506 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Carbonic anhydrase (CA) which catalyzes the reversible hydrolysis of carbon dioxide is known to be important in osteoclastic bone resorption, however, suggested roles in calcium phosphate mineral formation have not been previously demonstrated. Biochemical evidence is provided for the presence of CA in growth plate matrix vesicles (MV) and the level of activity determined by enzyme assay. Inhibition of CA activity with the specific inhibitor acetazolamide resulted in reduced rates of MV mineralization. Other inhibitor studies showed that MV mineralization was also impaired by 4,4-diisothiocyanatostilbene-2, 2-disulfonic acid (DIDS), a blocker of membrane bicarbonate channels. No evidence was found for the presence of any proton pumps or channels. When acetazolamide and DIDS were combined, their inhibitory effects on MV mineralization were additive. These findings suggest that MV possess a pH regulation system composed of carbonic anhydrase and a putative bicarbonate channel. This system may function in the MV by providing intraluminal buffering capacity. The control of intravesicular pH is important for the stabilization of the acid-labile nucleational core complex and in preventing the build-up of protons during calcium phosphate phase transformations. |
| | |
Authors:
|
G R Sauer; B R Genge; L N Wu; J E Donachy |
Related Documents
:
|
15699596 - Measurement of erythrocyte carbonic anhydrase isozymes (ca-i and ca-ii) in racehorses a... 10488246 - Carbonic anhydrase inhibitors. arylsulfonylureido- and arylureido-substituted aromatic ... 8037456 - Membrane-associated carbonic anhydrase from the crab gill: purification, characterizati... 8996 - H+ current response to co2 and carbonic anhydrase inhibition in turtle bladder. 10464266 - Nadh shuttle system regulates k(atp) channel-dependent pathway and steps distal to cyto... 8141766 - Intracellular ca2+, inositol 1,4,5-trisphosphate and additional signalling in the stimu... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
|
Title: Bone and mineral Volume: 26 ISSN: 0169-6009 ISO Abbreviation: Bone Miner Publication Date: 1994 Jul |
Date Detail:
|
Created Date: 1994-12-23 Completed Date: 1994-12-23 Revised Date: 2007-11-14 |
Medline Journal Info:
|
Nlm Unique ID: 8610542 Medline TA: Bone Miner Country: IRELAND |
Other Details:
|
Languages: eng Pagination: 69-79 Citation Subset: IM; S |
Affiliation:
|
Department of Chemistry and Biochemistry, University of South Carolina, Columbia 29208. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid
/
pharmacology Acetazolamide / pharmacology Animals Blotting, Western Calcification, Physiologic* Carbonic Anhydrases / metabolism* Chickens Electrophoresis, Polyacrylamide Gel Growth Plate / enzymology, metabolism* Hydrogen-Ion Concentration Intracellular Membranes / metabolism Microsomes / metabolism |
| Grant Support | |
ID/Acronym/Agency:
|
DE05513/DE/NIDCR NIH HHS; DE10196/DE/NIDCR NIH HHS |
| Chemical | |
Reg. No./Substance:
|
53005-05-3/4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; 59-66-5/Acetazolamide; EC 4.2.1.1/Carbonic Anhydrases |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Dual-energy X-ray absorptiometry for measuring total bone mineral content in the rat: study of accur...
Next Document: Dietary xylitol prevents ovariectomy induced changes of bone inorganic fraction in rats.