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Endothelin-converting enzyme and its in vitro and in vivo inhibition.
- Source :
-
Journal of cardiovascular pharmacology [J Cardiovasc Pharmacol] 1991; Vol. 17 Suppl 7, pp. S26-8. - Publication Year :
- 1991
-
Abstract
- We investigated endothelin (ET)-converting enzyme and its localization in the vasculature. The membrane and cytosol fractions of cultured endothelial cells of bovine carotid artery contain phosphoramidon-sensitive ET-converting enzymes, and their molecular weights are about 100 and 540 kDa, respectively. The specific conversion of big ET-1 by these enzymes proceeds at pH 7.0 +/- 0.5, and it is inhibited by EDTA, o-phenanthroline, and phosphoramidon. Big ET-3 is converted by the membrane enzyme at a rate about one-tenth that of big ET-1, but it is not converted by the cytosol enzyme. Big ET-1 (but not ET-1)-induced hypertension in rats was remarkably suppressed by pretreatment with phosphoramidon, and big ET-1 (but not ET-1)-induced contraction of isolated coronary arteries, either with or without the endothelium, was substantially suppressed by phosphoramidon. These results suggest an essential role of phosphoramidon-sensitive enzyme(s) in the vascular conversion of big ET-1, and the existence of such enzymes also in nonendothelial cells. We found three converting enzymes operating at different optimal pH values in noncultured vascular smooth muscle cells; two pepstatin-sensitive, cytosolic acid proteinases and a phosphoramidon-sensitive neutral enzyme(s) in the membrane and cytosol. All of these findings strongly suggest the importance of phosphoramidon-sensitive neutral enzymes in the vascular conversion of big ET-1.
- Subjects :
- Animals
Aspartic Acid Endopeptidases antagonists & inhibitors
Blood Pressure drug effects
Carotid Arteries enzymology
Cattle
Cell Membrane enzymology
Cells, Cultured
Cytosol enzymology
Endothelin-1
Endothelin-Converting Enzymes
Endothelins metabolism
Endothelins pharmacology
Endothelium, Vascular enzymology
Glycopeptides pharmacology
Humans
In Vitro Techniques
Metalloendopeptidases
Muscle Contraction drug effects
Muscle, Smooth, Vascular drug effects
Protein Precursors metabolism
Protein Precursors pharmacology
Rats
Swine
Aspartic Acid Endopeptidases metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0160-2446
- Volume :
- 17 Suppl 7
- Database :
- MEDLINE
- Journal :
- Journal of cardiovascular pharmacology
- Publication Type :
- Academic Journal
- Accession number :
- 1725349
- Full Text :
- https://doi.org/10.1097/00005344-199100177-00008