OBJECTIVES This study examined the effects of endotoxin on cardiac contractility in human myocardium. BACKGROUND In animal myocardium, endotoxin and cytokine treatment led to enhanced inducible nitric oxide synthase (iNOS) expression and contractile dysfunction. Effects in human myocardium are unknown. METHODS Left ventricular myocardial preparations from failing (n = 18) and nonfailing (n ...

Isolated brown adipose cells from rats are prepared whose viability is indicated by the expected stimulation of oxygen consumption by noradrenaline and counter-regulation of this oxygen consumption response by insulin. Insulin stimulates 3-O-methyl-D-glucose transport by approx. 15-fold in the absence of adenosine, and adenosine augments this response at least 2-fold. The insulin-stimulated tra...

The aim of this paper was to find out how pulmonary arterial hypertension (PAH) affects heart rate in male and female rats. Additionally, the concentration of tumor necrosis factor alpha (TNF-alpha) was monitored. Male and female rats were treated by monocrotaline (i.p., 60 mg/kg B.W.) or by equivalent volume of normal saline solution (n=40) and after 4 weeks right auriculae containing sinoatri...

The nonselective beta-adrenoceptor agonist, isoprenaline (pD2; 8.8 +/- 0.2), and selective beta2-adrenoceptor agonists, clenbuterol (9.2 +/- 0.4) and salbutamol (7.1 +/- 0.1), inhibited the immunoglobulin E-mediated release of histamine from human lung mast cells in a concentration-dependent manner. The beta2-adrenoceptor-selective antagonist, ICI118551 (erythro-(+/- )-1-(7-methylindan-4-yloyl)...

Airway relaxation in response to isoprenaline, sodium nitroprusside (SNP) and electrical field stimulation (EFS) was compared under static and dynamic conditions. The capacity of relaxants to reduce airway stiffness and, thus, potentially contribute to bronchodilation was also investigated. Relaxation responses were recorded in fluid filled bronchial segments from pigs under static conditions a...

Desensitization of adenylate cyclase-coupled beta-adrenergic receptors in avian erythrocytes results in a 40-65% decrease in agonist-stimulated adenylate cyclase activity and correlates with increased phosphorylation of beta-adrenergic receptors. To assess the role of phosphorylation in desensitization, membranes from isoprenaline- and dibutyryl cyclic AMP-desensitized turkey erythrocytes were ...

We studied the effects of oral propranolol administered in 2 low dose schedules (5 or 20 mg 8 hourly) and for a short term (30 to 36 hours) on heart rate, plasma renin activity, and arterial pressure, both at rest and after an isoprenaline challenge (8 mg i.v. over 2 min) in 6 normal subjects. Resting heart rate, plasma renin activity, and systolic pressure all fell significantly after the 5 mg...

1. The effect of endogenous sympathetic stimulation (induced by urinary bladder stimulation) and intravenous infusion of noradrenaline and isoprenaline on blood pressure, heart rate and levels of plasma renin activity and plasma aldosterone were studied in six tetraplegic patients. Data from infusion studies were compared with data from six normal subjects studied in an identical manner. 2. Bla...

It has been suggested that the use of a cumulative technique to obtain bronchodilator dose-response curves will cause a greater response than a non-cumulative technique, because sequential doses of drug will penetrate further into the lung. To test this hypothesis we have compared cumulative and non-cumulative dose-response curves for inhaled isoprenaline in 10 subjects with stable asthma, meas...

The aim of this study was to systematically compare the interaction of the long-acting beta2-adrenoceptor agonists formoterol and salmeterol with short-acting beta2-adrenoceptor agonists in contracted human bronchi. Human bronchi were obtained at thoracotomy from patients with lung cancer. Formoterol or salmeterol at concentrations inducing up to 92 and 94% of their maximal relaxant effect, res...