Safety of calcium antagonists: More ACTION

Vasodilator action of calcium antagonists in coronary arteries in vitro.

Calcium antagonists have routinely been assumed to inhibit the contractions of arterial smooth muscle through block of membrane channels. The effects of nifedipine and diltiazem on contractions were examined in in vitro preparations of cattle coronary artery, one of the key therapeutic targets of calcium antagonists, to determine if alternate mechanisms of action are involved. Contractions elic...

Clinical pharmacology of calcium antagonists. Satellite symposium on calcium antagonists.

A new class of agents has been made available for the treatment of hypertension. These calcium antagonists have rapid bioavailability and dramatic antihypertensive effects through reduction of total peripheral resistance and the vascular resistance of the major target organs of the body. These changes are usually associated with unchanged cardiac output, preserved organ blood flows, maintained ...

Inhibitory action of calcium antagonists on ATP-dependent calcium uptake by the renal cortical microsomes.

Effects of Ca2+ antagonists, verapamil and diltiazem, on uptake and release of Ca2+ by microsomes of the renal cortex were studied. Verapamil inhibited the ATP-dependent Ca2+ uptake by renal microsomes. Addition of 0.8 mM verapamil was required to produce 50% inhibition of the ATP-dependent CA2+ uptake. Diltiazem also depressed the Ca2+ uptake was not due to an increased permeability for Ca2+, ...

Atherosclerosis, calcium, and calcium antagonists.

A QUANTUM CHEMICAL STUDY OF STRUCTURE -ACTIVITY RELATIONSHIPS OF DIHYDROPYRIDINE CALCIUM ANTAGONISTS

Quantum chemical (MNDo)caleulations have beenused toelucidate the molecular properties and structure - activity relationships of dihydropyridine (DHP) type calcium antagonists. There is a good corielation between the net atomic charges on various atoms of the 4 - phenyl ring of dihydropyridines and pharmacological activity. .Also, activity decreases with increasing free rotation of the phen...