The dihydropyridine calcium channel blocker, nitrendipine, was studied for its effects on the sodium current of single cultured ventricular cells from neonatal rats. The patch-clamp method of recording whole cell currents was used, and sodium currents were isolated by suppressing potassium and calcium currents. Potassium currents were blocked by replacing potassium with cesium in the internal a...

BACKGROUND We wished to assess the respective roles of the antihypertensive and blood pressure (BP)-independent effects of antihypertensive drugs on arterial hemodynamics and left ventricular hypertrophy (LVH) in end-stage renal disease (ESRD) patients. METHODS AND RESULTS In a double-blind study, 24 ESRD patients with LVH were randomized to 12 months' administration of either the angiotensin...

3H]Nitrendipine binds with high affinity to brain membranes with a drug specificity indicating association with sites mediating the pharmacologic actions of dihydropyridine slow-calcium-channel antagonist drugs. In brain membranes, [3Hjnitrendipine binding is absolutely dependent on the presence of calcium ions. Interactions of cations with [3H]nitrendipine binding sites correlate with their ph...

OBJECTIVE To investigate the reasons for withdrawal from double-blind randomized trials, and the reasons for changing treatment within a randomized therapeutic group. DESIGN The Syst-Eur trial, in which 4695 older patients with systolic hypertension were randomized to active or placebo treatment. METHODS The reasons for withdrawal from the trial were examined, both for patient-initiated and...

To find the best timing for administration of long-acting antihypertensive drugs, we gave nitrendipine, a calcium antagonist of the dihydropyridine group, once a day to six hospitalized and drug-free patients with essential hypertension, changing the time of administration and studying the effects on the circadian rhythm of blood pressure. After control values of 24-hour blood pressure variatio...

OBJECTIVES The purpose of this study was to assess the effects of enalapril and nitrendipine on the cardiac sympathetic nervous system. BACKGROUND Angiotensin-converting enzyme inhibitors and long-acting calcium channel blockers have been widely used in the treatment of cardiovascular diseases, in some of which sympathetic overactivity plays a major role in the pathophysiology and prognosis. ...

Tetrandrine, a bis-benzylisoquinoline alkaloid derived from the Chinese medicinal herb Stephania tetrandra, is a putative Ca2+ entry blocker whose mechanism of action is unknown. To investigate this mechanism, the effects of tetrandrine were characterized on binding of three chemical classes of Ca2+ entry blockers in cardiac sarcolemmal membrane vesicles. In the range 25-37 degrees C, tetrandri...

To determine the specificity of the previously demonstrated competition of verapamil with radioligand binding to a-adrenergic receptors, we examined the interaction of calcium channel blockers with aiand a2-adrenergic receptors on several tissues. Verapamil competed for [H] prazosin binding to ai-adrenergic receptors and for [H]yohimbine binding to a2-adrenergic receptors in several tissues (hu...