Increased release of nitric oxide associated with nebivolol may counteract the detrimental effect of beta-blockade on penile erection, thereby allowing maintenance of sexual activity in previously untreated hypertensive men compared with a significant decrease observed in the sexual activity of men receiving atenolol-based treatment.

Results of this study indicate that lower serum PON1 activity is associated with oxidative stress and the activity of PON1 is not related to HDL-cholesterol.

Ischemia leads to impaired ATP metabolism, with increased production of purine degradation products, such as hypoxanthine and xanthine, which are useful markers of tissue hypoxia. These extracellular markers of ischemia have been studied extensively in many clinical conditions of oxidative stress, including perinatal asphyxia, acute respiratory distress syndrome, cerebral ischemia, and preeclampsia. The aim of this study was to explore the usefulness of urinary hypoxanthine and xanthine as ischemia markers in acute coronary syndromes. Urinary excretion of hypoxanthine and xanthine was assessed by high-performance liquid chromatography in 30 patients with acute coronary syndromes and in 30 age- and sex-matched controls. Serum and urine uric acid, creatinine, and urea concentrations were also determined. Hypoxanthine excretion was significantly elevated in patients compared with healthy controls (84.37+/-8.63 and 42.70+/-3.97 nmol/mg creatinine, mean+/-SEM, P<0.0001). Urinary xanthine levels were also increased in patients with acute coronary syndromes (100.13+/-12.14 and 34.74+/-4.07 nmol/mg creatinine patients and controls, respectively; P<0.0001). Hypoxanthine and xanthine excretion showed a strong positive correlation in both groups. Significant negative correlations between urinary hypoxanthine and uric acid and xanthine and uric acid were observed in the patients, but not in controls. In conclusion, increased levels of ATP degradation products hypoxanthine and xanthine are observed in various hypoxic clinical conditions. This study suggests that these parameters may be useful markers of ischemia in patients with acute coronary syndromes.

Objectives: Although the pathophysiology of syndrome X (angina pectoris, positive ECG test findings and normal coronary arteriogram) is unclear, it is generally accepted that intracellular metabolic changes resulting from abnormal constriction of prearteriolar vessels due to endothelium-dependent vasodilation abnormalities may play a role in the pathogenesis. We established the effect of long-term treatment with cilazapril, an angiotensin-converting enzyme inhibitor, which prevents the effect of angiotensin II in the tonic control of vascular resistance. Methods: 18 patients (15 women and 3 men, mean age 43.2 ± 4.6 years) with syndrome X were included in this study. A randomized double-blind crossover placebo-controlled trial was done. After a 1-week washout period, patients received either cilazapril 2 × 2.5 mg or placebo for 3 weeks, followed by 3 weeks of the other therapy. At the end of two periods, an exercise ECG test (modified Bruce protocol) was employed. Results: The magnitude of ST segment depression was significantly decreased during treatment with cilazapril compared with placebo. On the other hand, total exercise time and time to 1 mm ST segment depression were significantly prolonged by cilazapril. However, rate pressure products were not significantly different at peak exercise at or at 1 mm of ST segment depression during both therapies. Conclusion: Cilazapril exerted a beneficial therapeutic effect in cases with syndrome X. The possible mechanism of this effect may be a modulation of coronary tone at the microcirculation level.

The aim of this study was to estimate the incidence of silent myocardial ischaemia in patients with mild to moderate hypertension, white-coat hypertension (WCH) and those with normal blood pressure. Ambulatory electrocardiographic (ECG) monitoring was carried out in 272 cases with normal blood pressure, 164 cases with mild to moderate hypertension (diastolic blood pressure Ͼ95 and Ͻ114 mm Hg), and 106 cases with white-coat hypertension who were diagnosed with ambulatory blood pressure monitoring. The ages of the patients of all groups were between 42-61 years. There were no differences between the groups according to age, gender