Myocardial alpha 1-adrenergic receptor stimulation.
نویسندگان
چکیده
منابع مشابه
Effects of myocardial alpha 1-adrenergic receptor stimulation and blockade on contractility in humans.
BACKGROUND Although alpha-adrenergic receptors are present in both normal and failing human left ventricular myocardium and mediate a positive inotropic effect in several other species, it is not known whether stimulation of myocardial alpha-adrenergic receptors exerts a positive inotropic effect or contributes to basal contractile state in vivo in humans. METHODS AND RESULTS We studied 15 pa...
متن کاملSustained Alpha-adrenergic Stimulation
The effects of brief and sustained pharmacologic alpha-adrenergic stimulation on the coronary arterial circulation were compared in awake pigs. Phenylephrine was administered into the left anterior descending coronary artery (LAD) either as a bolus (eight pigs) or as a 15-minute infusion (eight pigs), with myocardial blood flow measured by the radioactive microsphere technique. Flow in the dist...
متن کاملDevelopmental changes in guanine nucleotide regulatory proteins in the rat myocardial alpha 1-adrenergic receptor complex.
During development, the cardiac alpha 1-adrenergic chronotropic response changes from positive in the neonate to negative in the adult. The negative chronotropic effect of alpha 1-adrenergic stimulation in the adult depends on maturation of sympathetic innervation and the presence of a pertussis toxin (PT)-sensitive guanine nucleotide-binding (G) protein. To examine the possibility of a develop...
متن کاملb-Adrenergic Receptor Kinase-1 Levels in Catecholamine-Induced Myocardial Hypertrophy Regulation by b- but not a1-Adrenergic Stimulation
Pressure overload ventricular hypertrophy is accompanied by dysfunctional b-adrenergic receptor signaling due to increased levels of the b-adrenergic receptor kinase-1, which phosphorylates and desensitizes b-adrenergic receptors. In this study, we examined whether increased b-adrenergic receptor kinase 1 expression is associated with myocardial hypertrophy induced by adrenergic stimulation. Wi...
متن کاملThe alpha-1D Is the predominant alpha-1-adrenergic receptor subtype in human epicardial coronary arteries.
OBJECTIVES The goal was to identify alpha-1-adrenergic receptor (AR) subtypes in human coronary arteries. BACKGROUND The alpha1-ARs regulate human coronary blood flow. The alpha1-ARs exist as 3 molecular subtypes, alpha1A, alpha1B, and alpha1D, and the alpha1D subtype mediates coronary vasoconstriction in the mouse. However, the alpha1A is thought to be the only subtype in human coronary arte...
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ژورنال
عنوان ژورنال: Circulation
سال: 1992
ISSN: 0009-7322,1524-4539
DOI: 10.1161/01.cir.85.5.1958