Activation of peroxisome proliferator-activated receptor-alpha by fenofibrate prevents myocardial dysfunction during endotoxemia in rats.

Objective: To investigate the effects of fenofibrate, an activator of peroxisome proliferator-activated receptor-alpha, on cardiac function in a rat endotoxemia model.

Design: Prospective, randomized, controlled study.

Setting: University research laboratory.

Effects of desflurane in senescent rat myocardium.

Background: The myocardial negative inotropic effects of desflurane are less pronounced than those of other halogenated anesthetics, partly because of intramyocardial catecholamine store release. However, the effects of desflurane on aging myocardium are unknown, whereas aging is known to be associated with an attenuation of catecholamine responsiveness.

Methods: The effects of desflurane (1.

Endotoxin-induced myocardial dysfunction in senescent rats.

Introduction: Aging is associated with a decline in cardiac contractility and altered immune function. The aim of this study was to determine whether aging alters endotoxin-induced myocardial dysfunction.

Methods: Senescent (24 month) and young adult (3 month) male Wistar rats were treated with intravenous lipopolysaccharide (LPS) (0.

Severe impairment of ventricular compliance accounts for advanced age-associated hemodynamic dysfunction in rats.

Advanced aging is associated with hemodynamic dysfunction in rats as in humans. The aim of this study was to assess the mechanisms of development of left ventricular (LV) dysfunction in the rat model of aging. In vivo hemodynamics and ex vivo LV papillary muscle mechanics, myofilaments sensitivity to calcium in skinned fibers and pressure/volume curves in isolated perfused hearts were performed in 3, 24 and 28 month old (mo) male Wistar rats.

Cardioprotection with cariporide, a sodium-proton exchanger inhibitor, after prolonged ischemia and reperfusion in senescent rats.

This study investigated the effects of cariporide, an inhibitor of sodium-proton exchanger (NHE), during myocardial ischemia and reperfusion in senescence. Isolated Langendorff perfused hearts from 4 (adult) and 24 (senescent) month old male Wistar rats were submitted to prolonged low-flow ischemia (LFI) at 15% of initial coronary flow (180 min) or to 45 min of LFI (15% of initial coronary flow) followed by 30 min of reperfusion, without or with cariporide (10(-6)M). In senescent hearts, but not in adults, treatment with cariporide during prolonged LFI attenuated the elevation of coronary resistances (578 +/- 84 vs 1020 +/- 129% of baseline value after 180 min, P < 0.

Myocardial effects of halothane and isoflurane in senescent rats.

Background: Aging is associated with marked alterations in myocardial contraction and relaxation, whereas halogenated anesthetics depress myocardial contractility. However, their effects on aging myocardium are unknown.

Methods: Mechanical variables of left ventricular papillary muscles from adult and senescent rats (29 degrees C; pH 7.