Augmentation of limb perfusion and reversal of tissue ischemia produced by ultrasound-mediated microbubble cavitation.

Background: Ultrasound can increase tissue blood flow, in part, through the intravascular shear produced by oscillatory pressure fluctuations. We hypothesized that ultrasound-mediated increases in perfusion can be augmented by microbubble contrast agents that undergo ultrasound-mediated cavitation and sought to characterize the biological mediators.

Methods And Results: Contrast ultrasound perfusion imaging of hindlimb skeletal muscle and femoral artery diameter measurement were performed in nonischemic mice after unilateral 10-minute exposure to intermittent ultrasound alone (mechanical index, 0.

Epoxyeicosatrienoic acids mediate insulin-mediated augmentation in skeletal muscle perfusion and blood volume.

Skeletal muscle microvascular blood flow (MBF) increases in response to physiological hyperinsulinemia. This vascular action of insulin may facilitate glucose uptake. We hypothesized that epoxyeicosatrienoic acids (EETs), a family of arachadonic, acid-derived, endothelium-derived hyperpolarizing factors, are mediators of insulin's microvascular effects.

Echocardiographic evaluation of the effects of stem cell therapy on perfusion and function in ischemic cardiomyopathy.

Background: Small animal models of ischemic left ventricular (LV) dysfunction are important for the preclinical optimization of stem cell therapy. The aim of this study was to test the hypothesis that temporal changes in LV function and regional perfusion after cell therapy can be assessed in mice using echocardiographic imaging.

Methods: Wild-type mice (n = 25) were studied 7 and 28 days after permanent ligation of the left anterior descending coronary artery.

Renal retention of lipid microbubbles: a potential mechanism for flank discomfort during ultrasound contrast administration.

Background: The etiology of flank pain sometimes experienced during the administration of ultrasound contrast agents is unknown. The aim of this study was to investigate whether microbubble ultrasound contrast agents are retained within the renal microcirculation, which could lead to either flow disturbance or local release of vasoactive and pain mediators downstream from complement activation.

Methods: Retention of lipid-shelled microbubbles in the renal microcirculation of mice was assessed by confocal fluorescent microscopy and contrast-enhanced ultrasound imaging with dose-escalating intravenous injection.