the purpose of the work presented here was to investigate endotheliumdependent relaxations in the rabbit coronary ligation model of heart failure. we investigated endothelium-dependent relaxations at the level of larger vessels (thoracic aorta and vena cava left renal artery and left renal vein lateral saphenous artery and lateral saphenous vein and finally central ear artery and marginal ear v...

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...

BACKGROUND Chronic stress-induced cardiac pathology exhibits both a wide range in severity and a high degree of heterogeneity in clinical manifestation in human patients. This variability is contributed to by complex genetic and environmental etiologies within the human population. Genetic approaches to elucidate the genetics underlying the acquired forms of cardiomyopathies, including genome-w...

The effects of chronic treatment with growth hormone (porcine GH, 0.56 mg ⋅ kg-1 ⋅ day-1sc) were examined in dogs with heart failure induced by rapid ventricular pacing (240 beats/min) for 4 wk. Fourteen conscious dogs were studied 2-3 wk after surgical instrumentation with catheters in the descending aorta and left atrium, a pressure gauge in the left ventricle (LV), a flow probe around the as...

SUMMARY The effects of practolol, a new beta-adrenergic blocking agent, and propranolol were studied in volunteers. At rest, practolol caused a very small reduction in cardiac index (CI), 190 ml, P < 0.25, and preejection period (PEP) lengthened 3 msec, P < 0.025. In contrast, propranolol caused a reduction in CI of 770 ml, P < 0.001. Heart rate (HR) slowed 10 beats/min, P < 0.001, stroke volum...

objective: the study was conducted to evaluate cardioprotective effect of silk cocoon (abresham) bombyx mori (b. mori) on isoprenaline-induced myocardial infarction. this study deals with the cocoons, which is called abresham in the unani system of medicine. it is one of the 64 drugs which avicenna has mentioned in avicenna’s tract on cardiac drugs and used in the treatment of cardiovascular di...

The excessive stimulation of beta-adrenergic receptors in the heart induces myocardial hypertrophy. There are several experimental data suggesting that this hypertrophy may also depend, at least partially, on the increase of local production of angiotensin II secondary to the activation of the cardiac renin-angiotensin system. In this study we investigated the effects of isoproterenol on the ac...

background : the signal-averaged electrocardiography is a noninvasive method to evaluate the presence of the potentials generated by tissues activated later than their usual timing in the cardiac cycle. the purpose of this study was to demonstrate the correlation between the filtered qrs duration obtained via the signal-averaged electrocardiography and left ventricular dimensions and volumes an...

We examined, in conscious dogs, the effects of /?-adrenergic stimulation on measurements of left circumflex coronary arterial diameter and blood flow and on calculations of late diastolic coronary resistance (LDCR) and left circumflex coronary internal cross-sectional area (CSA). Isoproterenol (0.1 fig/kg) initially decreased mean arterial pressure by 25 ± 2% (mean ± SEM), and LDCR by 62 ± 4%, ...

Substantial evidence suggests that the progressive loss of cardiomyocytes caused by apoptosis significantly contributes to the development of heart failure. beta-Adrenergic receptor activation and subsequent persistent phosphodiesterase 3A (PDE3A) downregulation and concomitant inducible cAMP early repressor (ICER) upregulation (PDE3A/ICER feedback loop) has been proposed to play a key role in ...