BACKGROUND This study investigated histopathological changes and apoptotic factors that may be involved in the renal damage caused by congestive heart failure in a rat model of infrarenal aortocaval fistula (ACF). METHODS Heart failure was induced using a modified approach of ACF in male Wistar rats. Sham-operated controls and ACF rats were characterized by their morphometric and hemodynamic ...

Aortocaval fistula (ACF)-induced volume overload (VO) heart failure (HF) results in progressive left ventricular (LV) dysfunction. Hemodynamic load reversal during pre-HF (4 wk post-ACF; REV) results in rapid structural but delayed functional recovery. This study investigated myocyte and myofilament function in ACF and REV and tested the hypothesis that a myofilament Ca(2+) sensitizer would imp...

Background—Whereas nitric oxide (NO) has been implicated in the pathophysiology of heart failure (HF), the significance and functional role of different NO synthase (NOS) isoforms in this pathology are controversial. Our aim was to study in the myocardium of rats with volume-overload–induced HF the expression, activity, and localization of endothelial (eNOS) and inducible (iNOS) isoforms and th...

OBJECTIVE We performed experiments using Neuregulin-1β (NRG-1β) treatment to determine a mechanism for the protective role derived from its beneficial effects by remodeling gap junctions (GJs) during heart failure (HF). METHODS Rat models of HF were established by aortocaval fistula. Forty-eight rats were divided randomly into the HF (HF, n = 16), NRG-1β treatment (NRG, n = 16), and sham oper...

The objectives of this study were to investigate the temporal response of left ventricular (LV) matrix metalloproteinase (MMP) activity and collagen volume fraction (CVF) induced by an aortocaval fistula and the role of cardiac mast cells in regulating MMP activity. LV tissue was analyzed for MMP activity, CVF, and mast cell number in rats euthanized at 0.5, 1, 2, 3, 5, 14, 21, 35, and 56 days....

OBJECTIVE To compare cardiac structural changes in experimental pressure and volume overload models. METHODS The study analysis included renovascular hypertensive rats (RVH, n = 8), normotensive rats with volume overload caused by an aortocaval fistula (ACF, n = 10) and control rats (CONT, n = 8). After four weeks, tail cuff blood pressure (SBP) was recorded. Rats were killed, the hearts were...

We studied the effect of chronic mechanical overloading on the isoenzyme composition of rat cardiac myosin in several experimental models: aortic stenosis (AS), aortic incompetence (AI), aortocaval fistula (ACF), overload of the non-infarcted area after left coronary ligation (INF), and overload of the spontaneously hypertensive rats (SHR). Samples of the left and right ventricles were isolated...

Increased numbers of mast cells have been reported in explanted human hearts with dilated cardiomyopathy and in animal models of experimentally induced hypertension, myocardial infarction, and chronic volume overload secondary to aortocaval fistula and mitral regurgitation. Accordingly, mast cells have been implicated to have a major role in the pathophysiology of these cardiovascular disorders...

After being anastomosed with the artery, vein graft is exposed to abruptly increased hemodynamic stresses. These hemodynamic stresses may change the profile of endothelial gap junction expression as demonstrated in the artery, which may subsequently play active roles in physiological adaptation or pathophysiological changes of the vein grafts. We investigated the endothelial expression of gap j...