1. The effect of catecholamines (adrenaline, noradrenaline, and isoprenaline) in combination with ƒ¿and ƒÀ-blocking agents (phentolamine and propranolol) on pregnant mouse myometrium was investigated. The catecholamines had an inhibitory action in this tissue, the minimal dose required to produce inhibition being 3•~10-9 (g/ml) for isoprenaline, <10-7 for adrenaline, and <10-6 for noradrenaline...

Ten patients with idiopathic hypertrophic subaortic stenosis were studied with right and transseptal left heart catheterization. All patients had the expected increases in subvalvular systolic gradients with isoprenaline infusion, amyl nitrite inhalation, exercise, and performance of the Valsalva manoeuvre. These stimulatory procedures were repeated after intravenous infusion of practolol (6oo ...

The magnitude and duration of effect of a single 40-mg oral tablet of oxprenolol on the tachycardias associated with motor-car driving, isoprenaline infusion, and walking were compared against placebo in six normal people by a double-blind study. The tachycardias due to driving and isoprenaline were both conspicuousy reduced for over eight hours; the magnitude and duration of the reduction in e...

A girl of 14 with the long QT syndrome (LQTS) and torsades de pointes is reported. Isoprenaline or adrenaline infusions induced torsades de pointes and inversion of the TU wave. Changes in the TU wave during isoprenaline infusion were used to select effective drugs to treat this patient. A beta blocker and calcium channel blocker were selected and the patient had no episodes of syncope for two ...

Pharmacological examinations of isolated auricles from Sepia officinalis were carried out to analyze the putative role of the monoaminergic transmitter/receptor system in the control of auricle function. In conjunction with histofluorescence studies and HPLC analyses, evidence of a double excitatory serotonergic and noradrenergic innervation of the auricles was obtained. Serotonin-induced posit...

BACKGROUND Enhanced sympathetic activity facilitates complex ventricular arrhythmias and fibrillation. The restitution properties of action potential duration (APD) are important determinants of electrical stability in the myocardium. Steepening of the slope of APD restitution has been shown to promote wave break and ventricular fibrillation. The effect of adrenergic stimulation on APD restitut...

1. The regulation of'K and ICa were studied in single cells isolated from bull-frog atrium using the whole-cell configuration of the patch clamp and a perfused patch pipette. 2. IK was increased approximately 50-100% and ICa was increased approximately 6-10 times by 1 /LM-isoprenaline, 5 jtM-forskolin, or internal perfusion with 30 ,UMcyclic AMP. The effects of cyclic AMP and isoprenaline were ...

UNLABELLED The counter-regulatory effect of adenosine, isoprenaline and selected cyclic AMP analogues on insulin-stimulated 3-O-methylglucose transport and insulin binding were studied in rat fat-cells. Isoprenaline alone had no consistent effect on glucose transport in the presence of maximally effective insulin concentrations. However, it decreased insulin binding by approx. 20% and increased...