Sex differences in myocardial oxygen and glucose metabolism.
J Nucl Cardiol
; 14(4): 573-81, 2007 Jul.
Article
em En
| MEDLINE
| ID: mdl-17679067
ABSTRACT
BACKGROUND:
Both physiologic and pathophysiologic conditions affect the myocardium's substrate use and, consequently, its structure, function, and adaptability. The effect of sex on myocardial oxygen, glucose, and fatty acid metabolism in humans is unknown. METHODS ANDRESULTS:
We studied 25 young subjects (13 women and 12 men) using positron emission tomography, quantifying myocardial blood flow, myocardial oxygen consumption (MVO2), and glucose and fatty acid extraction and metabolism. MVO2 was higher in women than in men (5.74 +/- 1.08 micromol x g(-1) x min(-1) vs 4.26 +/- 0.69 micromol x g(-1) x min(-1), P < .005). Myocardial glucose extraction fraction and utilization were lower in women than in men (0.025 +/- 0.019 vs 0.062 +/- 0.028 [P < .001] and 133 +/- 96 nmol x g(-1) x min(-1) vs 287 +/- 164 nmol x g(-1) x min(-1) [P < .01], respectively). There were no sex differences in myocardial blood flow, fatty acid metabolism, or plasma glucose, fatty acid, or insulin levels. Female sex was an independent predictor of increased MVO2 (P = .01) and decreased myocardial glucose extraction fraction and utilization (P < .005 and P < .05, respectively). Insulin sensitivity was an independent predictor of increased myocardial glucose extraction fraction and utilization (P < .01 and P = .01, respectively).CONCLUSIONS:
Further studies are necessary to elucidate the mechanisms responsible for sex-associated differences in myocardial metabolism. However, the presence of such differences may provide a partial explanation for the observed sex-related differences in the prevalence and manifestation of a variety of cardiac disorders.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Oxigênio
/
Glucose
/
Miocárdio
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
J Nucl Cardiol
Assunto da revista:
CARDIOLOGIA
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Estados Unidos