Endothelin (ET) is a potent vasoconstrictor and sodium-regulating peptide whose tissue and plasma concentrations are increased in congestive heart failure (CHF). ET may mediate its vasoconstrictor and sodium-regulatory actions secondary to an increase in intracellular calcium. Calcium influx may augment ET synthesis. Although felodipine, a dihydropyridine calcium-channel antagonist, is effectiv...

UNLABELLED Aims Ingestion of grapefruit juice (GFJ) alters the pharmacokinetics of various orally administered drugs. Quantitative evaluation of this GFJ-drug interaction is required for the proper clinical management of patients. Methods Using felodipine as a model drug, we constructed a pharmacokinetic model based on irreversible inhibition of intestinal cytochrome P450 3A4 (CYP3A4) by GFJ. W...

A vascular selective calcium antagonist, felodipine, was evaluated in a randomised, double blind, crossover trial in 18 patients with chronic congestive heart failure of ischaemic cause. Felodipine (10 mg twice daily) or a corresponding placebo was added to conventional treatment. After three weeks haemodynamic function was assessed at rest, during a standard supine leg exercise, and during 45 ...

The acute effects of felodipine on left ventricular function and haemodynamics were studied in 11 patients with coronary artery disease. To block reflex sympathetic activation due to peripheral vasodilatation and to avoid effects secondary to changes in heart rate all patients received a standard regimen of beta adrenoceptor blockade and all measurements were made during sinus rhythm and right ...

The effects of long-term monotherapy with felodipine, a calcium antagonist, on blood pressure, glucose tolerance, and serum lipid profiles were prospectively investigated in 51 hypertensive patients: 13 with normal glucose tolerance and 38 with glucose intolerance. The levels of plasma glucose, serum lipids, and glycosylated hemoglobin A1c were determined before and during long-term (7.5 +/- 0....

PURPOSE Indapamide, a non-thiazide antihypertensive diuretic agent, has been widely coadministered with other classes of antihypertensive agents to reach target systolic blood pressure. Indapamide is extensively metabolized by cytochromes P450. Interaction of indapamide and other antihypertensive drugs are unknown. We investigated the effects of other antihypertensive drugs on the metabolism an...

purpose of this study was to investigate the effect of the presence of the water soluble polymers viz hpmc, pvp and peg 6000 on aqueous solubility and complexation abilities of felodipine with or without presence of β-cyclodextrin (βcd) and hpβcd by phase solubility studies. the data revealed the initial increase in drug solubility followed by plateau in the presence of relatively low polymer c...

In an earlier study one dose of the vasodilator felodipine improved haemodynamic function in patients with angina without having a negative inotropic effect. The haemodynamic response of sustained treatment with felodipine as a single agent in stable angina was investigated in a double blind crossover study of 25 patients. The dosage of felodipine was increased from 5 mg twice daily to 10 mg tw...

Homeostasis of intracellular calcium is crucial for lens cytoarchitecture and transparency, however, the identity of specific channel proteins regulating calcium influx within the lens is not completely understood. Here we examined the expression and distribution profiles of L-type calcium channels (LTCCs) and explored their role in morphological integrity and transparency of the mouse lens, us...

BACKGROUND Grapefruit juice (GFJ) enhances the systemic exposure of numerous CYP3A4 drug substrates, including felodipine, by inhibiting intestinal (but not hepatic) first-pass metabolism. Furanocoumarins have been identified as major CYP3A4 inhibitors contained in the juice, but their contribution to the GFJ effect in vivo remains unclear. OBJECTIVE To ascertain whether furanocoumarins media...