Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. We previously found that adrenaline and noradrenaline exert essentially opposite effects on clearance from plasma of chylomicron-like emulsions injected intravenously in rats, suggesting mechanisms that may be implicated in the atherogenic effects of chronic stress and hypertension and conversely in the protective effect of regular exercise. 2. The mechanisms underlying the effects of adrenaline and noradrenaline have now been investigated. Chronic adrenergic blockade with either the alpha 1-receptor antagonist doxazosin or the beta-receptor antagonist propranolol slowed the clearance of labelled emulsion lipids from plasma of normal Wistar rats. The results with doxazosin were unexpected in view of its capacity to decrease plasma triglycerides in patients. 3. In spontaneously hypertensive rats (SHR) the clearance of triolein (TO) was very slow compared with normal Wistar rats. Emulsion TO clearance provides a measure of lipolysis by lipoprotein lipase, and a defect in clearance indicates either defective enzyme action or poor perfusion of capillary beds rich in enzyme. Defective enzyme activity in SHR was excluded, suggesting redistribution of blood flow away from skeletal muscle and adipose tissue. In SHR the TO clearance from injected chylomicron-like emulsions was improved by blockade with doxazosin compared with control untreated SHR. 4. The beta 2-adrenoreceptor agonist Fenoterol was infused intravenously during clearance of an injected lipid emulsion. Clearance of radiolabelled cholesteryl oleate (CO) was clearly slowed while there was a lesser reduction of TO clearance rate. Emulsion CO clearance provides a measure of the uptake of lipoprotein remnants by the liver, and a defect in clearance of CO indicates either defective ligand (apolipoprotein E)-receptor interaction or decreased perfusion of the splanchnic bed. Isoprenaline, a non-selective beta-adrenergic agonist, gave similar results. Both compounds reduced mean arterial pressure by about 20-40 mm Hg at the doses employed, indicating that the beta 1 (cardiac) effect of the isoprenaline was insufficient to offset its vasodilatatory effect on skeletal muscle arterioles (beta 2). 5. The alpha-agonist phenylephrine, at a dose which moderately raised mean arterial pressure, slowed clearance of both TO and CO for the first 12 min after injection of emulsion but at later time points clearances caught up with the controls. 6. Administration of a mixture of isoprenaline and phenylephrine produced definite enhancement of both TO clearance and CO clearance. The effect of the mixture was opposite to the effects of of either agonist alone, demonstrating clearly that direct effects on lipoprotein lipase activity or receptor mediated processes were not involved.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of adrenoreceptor antagonists and agonists on clearance of emulsion models of triacylglycerol-rich lipoproteins from plasma in rats. 168 47

Airway resistance at term pregnancy was evaluated by oscillation technique in 15 hypertensive and 15 normotensive late pregnant women, and in 10 non-pregnant women. The recordings were obtained before and 1, 3, 6 and 12 min after administration of 0.6 mg Fenoterol by dose aerosol. - The Fenoterol-induced decrease of airway resistance was twice as large in pregnant women with hypertension as in the other two groups.
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PMID:[Increased sensitivity of the bronchial system of hypertensive pregnant patients to beta-adrenergic stimulation]. 298 82

Thirty-seven asthmatic adults (27 women, 10 men), aged 28 to 70 yrs (mean 50. yrs), in a stable condition, were studied to assess the cardiac tolerance of B2SM sprays. These patients had no cardiac arrhythmia (checked by echocardiography), no hypertension and no hyperthyroidism. Two thirds had severe asthma, and 16 suffered from chronic asthma. After their condition was stabilized, they continued their previous treatment, consisting of theophylline (34 cases), moderate corticotherapy (19 cases), atropine spray (14 cases). Holter monitoring was performed before and 3 days after the institution of treatment by Fenoterol spray at 1,600 micrograms per day in 4 doses at fixed times. Gasometry was tested immediately before and during the protocol. Before B2SM treatment, 26 patients had a normal Holter, 11 had an abnormal first recording (4 important atrial ectopic beats (EBs), 5 ventricular EBs, 1 associating the two), 1 patient had an episode of ventricular tachycardia (VT). With Fenoterol, we observed (with no clinical manifestation) the aggravation of 1 pre-existing atrial EBs and 2 ventricular EBs. Two patients had a short episode of tachycardia but the role of Fenoterol was uncertain: one case was an elderly hypoxaemic patient and in the second a high theophylline level (20 mg/l) was found. The arrhythmogenic property peculiar to B2SM in spray form seems low at the dose we used. However in this study and in certain circumstances, such as hypoxemia, metabolic acidosis, or theophylline overload, the use B2SM may have contributed, together with other factors, to induce disquieting infraclinical cardiac dysrhythmia. We stress that this short-term study involved stable asthmatic patients under surveillance in hospital conditions.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Cardiac tolerance of a beta 2-sympathomimetic spray in 37 asthmatic adults monitored by Holter recording]. 313 19