Clinical and experimental pharmacology & physiology
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Clin. Exp. Pharmacol. Physiol. · Jul 1999
Hypertension and insulin resistance: role of peroxisome proliferator-activated receptor gamma.
1. Insulin resistance has been highlighted as a common causal factor for hypertension, hyperlipidaemia, diabetes mellitus and obesity, all of which are recognized to occur simultaneously, and a distinct clinical entity is defined as 'multiple risk factor syndrome'. 2. Recently, a new class of antidiabetic agents, thiazolidinediones (TZD) has been developed and has been shown to improve insulin resistance by binding and activating a nuclear receptor, peroxisome proliferator-activated receptor (PPAR) gamma. 3. cDNA of rat PPAR gamma 1 and gamma 2 were cloned and gene regulation of PPAR gamma in rat mature adipocytes was examined. ⋯ The administration of TZD stimulated the endothelial secretion of type-C natriuretic peptide, which is one of the natriuretic peptide family and is demonstrated by us to act as a novel endothelium-derived relaxing peptide. 9. Concomitantly, TZD significantly suppressed the secretion of endothelin, a potent endothelium-derived vasoconstricting peptide. 10. Thiazolidinediones can affect vascular tone and growth by modulating the production of endothelium-derived vasoactive substances to influence occurrence and progression of hypertension and atherosclerosis.
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Clin. Exp. Pharmacol. Physiol. · May 1999
Comparative StudyComparison of oscillometric blood pressure measurements at the wrist with an upper-arm auscultatory mercury sphygmomanometer.
1. Oscillometric devices for blood pressure (BP) measurement at the wrist are becoming more widely used in clinical practice. However, systematic comparisons with standard auscultatory BP measurement at the brachial artery are scarce. ⋯ For the Omron R3, fixed or proportional error was not detected for either systolic or diastolic BP. 6. These wrist oscillometric devices, although offering portability and convenience, give BP measurements that frequently differ substantially (by at least 5 mmHg) from readings simultaneously measured at the upper arm by a mercury sphygmomanometer. The magnitude and direction of differences detected are dependent on both the device used and the underlying level of BP.
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1. Sepsis is the leading reversible cause of death in patients requiring modern intensive care services. 2. ⋯ As septic shock is the most common early manifestation of severe sepsis, an understanding of mechanisms of myocardial dysfunction is of clinical relevance. In the present review, we will discuss mechanisms of remote organ failure in sepsis, focusing in particular on the pathogenesis of myocardial dysfunction.
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Clin. Exp. Pharmacol. Physiol. · Nov 1998
ReviewCerebrovascular pressure transmission analysis as a guide to the pathophysiology of raised intracranial pressure.
1. Raised intracranial pressure (ICP) is a major factor associated with morbidity and mortality in patients with severe head injury. Identifying the mechanisms responsible for raised ICP may be difficult and, as a result, treatment prescribed may be non-specific and often ineffective. 2. ⋯ Laboratory models have identified specific CVPT patterns associated with various causes of raised ICP. These studies have been extended to clinical practice and have been used to define patterns of CVPT in head-injured patients, which may be used to identify mechanisms responsible for raised ICP, thus assisting in directing treatment strategy. Clinical usefulness of this technique in patient management is currently under investigation.
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Clin. Exp. Pharmacol. Physiol. · Jul 1998
Effects on hypoxaemia on foetal heart rate, variability and cardiac rhythm.
1. Experiments were carried out in 30 chronically catheterized foetal sheep (128-144 days; term 150 days) and in seven of these foetuses before, during and after acute hypoxaemia. The extent to which changes in sympathoadrenal activity and cardiac vagal activity affected the foetal cardiac response to hypoxaemia was measured. ⋯ Therefore, this increased sympathetic influence on the foetal heart during hypoxaemia must be predominantly the result of increased adrenomedullary secretion of catecholamines. 8. Maintenance of foetal cardiac output depends on the chronotropic and ionotropic effects of catecholamines. Therefore, this adrenomedullary influence on the foetal heart during hypoxaemia is important to offset the opposing effects of increased cardiac vagal tone.