Increased tissue angiotensin-converting enzyme activity impairs bradykinin-induced dilation of coronary arterioles in obesity.
Circ J
; 77(7): 1867-76, 2013.
Article
em En
| MEDLINE
| ID: mdl-23603844
ABSTRACT
BACKGROUND:
Bradykinin (BK) is a key mediator regulating coronary blood flow. It is degraded by angiotensin-converting enzyme (ACE), but what is unknown is whether enhanced tissue ACE activity interferes with BK-induced coronary vasodilation in obesity. METHODS ANDRESULTS:
Coronary arterioles (~100 µm) were isolated from rats on a normal or high-fat diet (HFD) and from lean or obese patients undergoing heart surgery (n=74). We found that BK-induced dilation was diminished in the coronary arterioles of HFD rats, when compared with controls. When administered in vitro, the ACE inhibitor, captopril, restored the coronary dilation response to BK in HFD rats, but did not affect control responses. Abundant ACE expression was detected in coronary endothelium, which was associated with increased ACE activity in HFD arterioles, as measured by increased response to the ACE substrate, angiotensin I. Moreover, we found that in the coronary arterioles of obese patients, BK-induced dilation was augmented by in vitro captopril administration. Correspondingly, ACE activity was increased in the coronary arterioles of obese patients when compared with the non-obese. Logistic regression analysis revealed that obese patients taking ACE inhibitors prior to surgery exhibited an enhanced dilation response to BK.CONCLUSIONS:
We demonstrated augmented tissue ACE activity in the coronary arterioles of obese subjects, which leads to reduced coronary dilation response to BK. We provide a rationale for ACE inhibitor therapy in obese patients to improve dilatation of coronary microvessels.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Vasodilatação
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Vasodilatadores
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Bradicinina
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Endotélio Vascular
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Peptidil Dipeptidase A
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Vasos Coronários
Limite:
Aged
/
Animals
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Female
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Circ J
Assunto da revista:
ANGIOLOGIA
/
CARDIOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos