It is thus conceivable that a lack of NOSs results in the development of left ventricular hypertrophy in mice in vivo. Recent clinical studies have revealed that electrocardiographically

determined left ventricular hypertrophy is a risk factor for cardiovascular death not only in hypertensive patients, but also in normotensive subjects (44) and (45). However, the underlying mechanisms remain to be elucidated. Based on our research outcomes obtained from the triple NOSs null mice, we have recently tested our hypothesis that normotensive subjects with electrocardiographically determined left ventricular hypertrophy have reduced NO production (46). AP24534 concentration The plasma NOx levels were markedly more reduced in normotensive males with electrocardiographically

determined left ventricular hypertrophy than in those without. In addition, the plasma NOx levels were inversely associated with the prevalence and severity of electrocardiographically determined left ventricular hypertrophy. These findings suggest that normotensive individuals with electrocardiographically determined left ventricular hypertrophy exhibit defective NO production. Our findings may thus explain, at least in part, a potential mechanism underlying the increased buy Panobinostat risk of cardiovascular death in normotensive subjects with electrocardiographically determined left ventricular hypertrophy. It is interesting to note that the observations in the triple NOSs null mice could be translated to the human subjects. Heart failure is a leading cause of morbidity and mortality in industrialized countries (47) and (48). There is growing recognition that not only systolic heart failure but also

diastolic heart failure with normal systolic function is common and causes significant morbidity and mortality. Indeed, recent studies have revealed that as many as 30-50% of patients with congestive heart failure have diastolic Etomidate heart failure, and that the morbidity and mortality rates for diastolic heart failure are nearly identical to those for systolic heart failure in aged patients (49). At 5 months of age, but not at 2 months of age, significant left ventricular diastolic dysfunction (as evaluated by echocardiographic E/A wave ratio and hemodynamic −dP/dt and Tau), with preserved left ventricular systolic function (as assessed by echocardiographic fractional shortening and hemodynamic +dP/dt) (Fig. 6), was noted only in the triple NOSs null mice, and this was associated with enhanced left ventricular end-diastolic pressure and increased lung wet weight, all of which are characteristics consistent with diastolic heart failure in humans (43).