decreased cardiac responsiveness to adrenergic stimulation has been observed in cholestatic liver disease, but the cause remains unclear. previous reports have suggested that nitric oxide overproduction might have a role in cholestasis-induced bradycardia via inhibition of l-type calcium channels. in the present study, the digoxin has been used to increase cardiac ca2+ transient in male sprague...

objectives in order to provide a pharmacological profile for some newly synthesized dihydropyridines, we investigated their effects on the isolated rat colon segments and the isolated rat atrium contractility. the tested compounds include alkyl ester analogues of nifedipine, in which the ortho-nitrophenyl group at position 4 is replaced by 2-alkylthio-1-benzyl-5-imidazolyl substituent, and nife...

Objectives In order to provide a pharmacological profile for some newly synthesized dihydropyridines, we investigated their effects on the isolated rat colon segments and the isolated rat atrium contractility. The tested compounds include alkyl ester analogues of nifedipine, in which the ortho-nitrophenyl group at position 4 is replaced by 2-alkylthio-1-benzyl-5-imidazolyl substituent, and nif...

This study used an isolated right atrial preparation, cross-perfused with arterial blood from a support dog. We investigated the effects of dibutyryl cyclic AMP (DBcAMP) on heart rate and arterial blood pressure of the support dog and on the sinus rate and atrial contractile force of the isolated perfused atrium. DBcAMP was injected into the external jugular vein of the support dog or into the ...

A one day old baby who presented with cyanosis was later shown to have an isolated persistent left superior vena cava draining into the left atrium with hypoplastic right superior vena cava. This extremely rare anomaly was diagnosed by cardiac catheterisation at one week. Surgical correction at two weeks, by anastomosis of the innominate vein to the right atrium and by ligation of the left supe...

  Among the present classes of calcium channel blockers, dihydropyridine derivatives are widely used in the therapy of hypertension, angina pectoris and the other cardiovascular diseases. Since the prototype of dihydropyridine derivatives, nifedipine, does not have the optimum pharmacokinetic and pharmacodynamic characteristics, several attempts have been made to synthesize other drugs in this ...

An asymptomatic patient with cardiomegaly caused by isolated right atrial standstill is reported. The right atrium showed no evidence of contraction on pressure records or angiographically, while the left atrium functioned normally.

In the isolated, blood-perfused dog atrium, strychnine evoked dose-dependent decreases in atrial rate and contractile force, and the negative cardiac effects were not influenced by atropine. Strychnine suppressed dose-dependently the negative chronotropic and inotropic responses to intramural parasympathetic nerve stimulation, but not the response to acetylcholine. These results suggest that st...

We tested the hypothesis that while absolute extrasystolic (ES) and postextrasystolic (PES) dP/dtmax would be influenced by pacing site, if these values were normalized by the steady-state dP/dtmax obtained with the same pacing site, they would be independent of pacing site. We employed an isovolumetrically contracting isolated heart preparation with a balloon placed in the left ventricle. Paci...