Disease relevance of Tiapamil hydrochloride

• Tiapamil, a new calcium antagonist: hemodynamic effects in patients with acute myocardial infarction [1].
• Thus, tiapamil, and not verapamil, decreased ischemic ventricular fibrillation while maintaining left ventricular mechanical function [2].
• Eleven patients, with recurrent paroxysmal supraventricular tachycardias (PSVT) underwent programmed electrical stimulation of the heart to evaluate the efficacy of intravenous (i.v.) and oral tiapamil in these arrhythmias [3].
• Efficacy of incremental doses of tiapamil on exercise performance in patients with chronic stable angina pectoris [4].
• Effect of i.v. and oral tiapamil in the treatment of paroxysmal supraventricular tachycardia [3].

High impact information on Tiapamil hydrochloride

• Antiarrhythmic and hemodynamic effects of the calcium channel antagonist verapamil were compared with those of tiapamil, a congener, in open-chest pigs with anterior descending coronary artery ligation [2].
• Verapamil and tiapamil in prevention of ventricular fibrillation in pigs with coronary ligation. Comparative effects on left ventricular function [2].
• Tiapamil decreased diastolic blood pressure and systemic and splanchnic vascular resistance [5].
• Tiapamil is safe and highly effective in improving exercise tolerance and relieving myocardial ischaemia in patients with chronic stable angina [4].
• Effects of the calcium antagonist tiapamil on pulmonary gas exchange in patients with chronic obstructive pulmonary disease who receive salbutamol [6].

Chemical compound and disease context of Tiapamil hydrochloride

• Comparative effects of prolonged therapy with four calcium ion antagonists (diltiazem, nicardipine, tiapamil and verapamil) in patients with chronic stable angina pectoris [7].
• In the presence of critical coronary stenosis, tiapamil and nifedipine produced similar magnitudes of decreases in blood pressure and changes in heart rate [8].
• Chronic hemodynamic effects of tiapamil and felodipine in essential hypertension at rest and during exercise [9].
• To clarify the pharmacological profile of the two new calcium channel blockers tiapamil and nisoldipine in humans, their acute effects as compared with those of the reference agent nifedipine were assessed in 10 normal subjects and 10 patients with essential hypertension [10].
• The hemodynamic effects exerted by two chemically dissimilar calcium antagonists (tiapamil and nifedipine) were studied in anesthetized dogs during control conditions, following critical stenosis of the left circumflex coronary artery, and in the presence of beta-receptor blockade with nadolol (1 mg/kg) [8].

Biological context of Tiapamil hydrochloride

• There is no evidence that tiapamil increases beta 2-agonist-induced impairment in pulmonary gas exchange [6].
• After partial depolarisation with a K+-rich tyrode solution (19 mmol X litre-1 K+). tiapamil lowers the Ca2+-dependent contractile force as it reduces the bioelectric parameters (upstroke velocity, amplitude, duration) of the Ca2+-mediated action potentials [11].
• In addition, tiapamil appreciably decreased heart rate and blood pressure and increased cardiac output and stroke volume [12].
• The binding sites discriminate between the diastereoisomers l- and d-cis-diltiazem, reconize verapamil, gallopamil and tiapamil, and are sensitive to La3+-inhibition [13].
• Similar changes in blood pressure and heart rate were not seen in patients receiving tiapamil [14].

Anatomical context of Tiapamil hydrochloride

• Moreover, in partially depolarised myocardium, the Mg2+-induced bioelectric membrane activity is suppressed by tiapamil [11].
• In isolated electrically stimulated guinea pig papillary muscles tiapamil exerts a negative inotropic action that corresponds to its presumptive inhibitory effects on the slow-channel-mediated transmembrane Ca2+ influx [11].
• The modification of high affinity [3H]BAY K 8644 binding by verapamil, diltiazem, tiapamil, Ca++ and EDTA appeared to be the same as that for nitrendipine binding, consistent with the hypothesis that the high affinity binding site for [3H]BAY K 8644 on isolated membranes is the same as the 1,4-dihydropyridine antagonist binding site [15].
• Excretion of tiapamil in breast milk [16].
• Tiapamil reduces the calcium inward current of isolated smooth muscle cells. Dependence on holding potential and pulse frequency [17].

Associations of Tiapamil hydrochloride with other chemical compounds

• To prevent the development of typical multidrug resistance, an inhibitor of P-glycoprotein, the tiapamil analog, RO-11-2933, was added to the selections [18].
• Bioelectrical and mechanical effects of tiapamil (Ro 11-1781) on isolated guinea pig myocardium [11].
• Novel dithiane analogues of tiapamil with high activity to overcome multidrug resistance in vitro [19].
• The multidrug resistance modifying activity of a dithiane analogue of tiapamil, Ro 44-5912, was examined in vivo [20].
• Mean plasma digoxin levels increased significantly in patients receiving tiapamil (P less than 0.01), but the values returned to normal after treatment with the experimental drug was discontinued [14].

Gene context of Tiapamil hydrochloride

• Tiapamil led to a decrease in mean daytime systolic (SBP) and diastolic (DBP) BP from 171 +/- 12/98 +/- 10 mm Hg to 159 +/- 11/90 +/- 9 mm Hg (P less than 0.001) without significant variation in HR [21].

Analytical, diagnostic and therapeutic context of Tiapamil hydrochloride

• The hemodynamic effects of this drug (1 mg/kg followed by 25 micrograms/kg/min over 36 hr) were studied in 30 patients randomly assigned in a double-blind manner to a tiapamil or control group within 12 hr of the onset of acute myocardial infarction as diagnosed by Swan-Ganz catheterization and gated blood pool scans [1].
• Tiapamil is effective during sympathetic stimulation and myocardial ischaemia but not during reperfusion [22].
• In contrast, in the dogs pretreated with tiapamil, ventricular fibrillation did not develop during coronary occlusion in any of the 11 dogs and did develop after coronary reperfusion in only one (9%) [12].
• The antihypertensive effect of a single oral dose of tiapamil (450 mg) and placebo were compared in a single blind randomized cross-over study in 10 71-86 year old hypertensive patients [21].
• Determination of tiapamil and of its two main metabolites in plasma and in urine by high-performance liquid chromatography [23].

References