Catecholamine-induced vasoconstriction is sensitive to carbonic anhydrase I activation.
Braz J Med Biol Res
; 34(3): 339-45, 2001 Mar.
Article
em En
| MEDLINE
| ID: mdl-11262584
We studied the relationship between alpha- and beta-adrenergic agonists and the activity of carbonic anhydrase I and II in erythrocyte, clinical and vessel studies. Kinetic studies were performed. Adrenergic agonists increased erythrocyte carbonic anhydrase as follows: adrenaline by 75%, noradrenaline by 68%, isoprenaline by 55%, and orciprenaline by 62%. The kinetic data indicated a non-competitive mechanism of action. In clinical studies carbonic anhydrase I from erythrocytes increased by 87% after noradrenaline administration, by 71% after orciprenaline and by 82% after isoprenaline. The increase in carbonic anhydrase I paralleled the increase in blood pressure. Similar results were obtained in vessel studies on piglet vascular smooth muscle. We believe that adrenergic agonists may have a dual mechanism of action: the first one consists of a catecholamine action on its receptor with the formation of a stimulus-receptor complex. The second mechanism proposed completes the first one. By this second component of the mechanism, the same stimulus directly acts on the carbonic anhydrase I isozyme (that might be functionally coupled with adrenergic receptors), so that its activation ensures an adequate pH for stimulus-receptor coupling for signal transduction into the cell, resulting in vasoconstriction.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vasoconstrição
/
Catecolaminas
/
Anidrases Carbônicas
/
Agonistas alfa-Adrenérgicos
/
Agonistas Adrenérgicos beta
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
/
Animals
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Braz J Med Biol Res
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Romênia
País de publicação:
Brasil