Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To study how acetylation affects the activity of sympathomimetic amines the effects of tyramine, amphetamine, ephedrine, phenylephrine, orciprenaline and salbutamol and of their O- and N-acetyl derivatives on blood glucose and free fatty acid concentrations were studied in the rabbit. Hyperglycemia was induced by all parent compounds except amphetamine which tended to have a weak hypoglycaemic action. Hyperlipaemia in the doses used was induced by ephedrine and orciprenaline but not by the other parent compounds. Usually acetylation decreased the metabolic effects of the compounds but O-acetylation of tyramine and salbutamol caused hyperlipaemia and O-acetylation of ephedrine increased its fatty acid-mobilizing action, perhaps as a consequence of increased lipid solubility of the compounds. The ultimate effects of the O-acetyl derivatives were probably at least partly due to deacetylation at their sites of action. However O-acetylation of sympathomimetics could perhaps be used to induce drug latentiation.
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PMID:Metabolic actions of some sympathomimetic amines and their acetyl derivatives in the rabbit. 57 60

The metabolic effects of celiprolol, a new beta-adrenoceptor blocking agent with intrinsic sympathomimetic activity and alpha 2-blocking properties, were evaluated in a series of patients with hypertension, both with and without hyperlipidemia. Propranolol was tested as the reference drug in a randomized double-blind trial. Of the 35 patients of both sexes who completed the study, 17 were hyperlipidemic (low-density lipoprotein cholesterol greater than or equal to 170 mg/dl) and 18 were normolipidemic. Both drugs exerted a similar hypotensive effect after gradual dose adjustment; however, propranolol reduced heart rate to a higher extent (-20.5%) than celiprolol (-7.7%). Propranolol determined a significant rise of total and very low-density lipoprotein (VLDL) associated triglyceridemia, whereas high-density lipoprotein cholesterol (HDL cholesterol) levels and the total cholesterol/HDL cholesterol ratios were significantly depressed, particularly in hyperlipidemic patients. Celiprolol, in contrast, slightly decreased triglyceridemia (significantly in the hyperlipidemic group at week 12) and caused a 5% increase of the HDL cholesterol levels. The total cholesterol/HDL cholesterol ratio was reduced by celiprolol at week 16 in both hyperlipidemic and normolipidemic patients. The effects of the two beta-adrenoceptor blockers on HDL cholesterol and triglyceride levels differed significantly after 12 and 16 weeks of treatment, which confirm the divergent metabolic effects of the two agents.
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PMID:Lipid effects of celiprolol, a new cardioselective beta-blocker, versus propranolol. 256 18

Almost all beta-adrenergic blockers, regardless of their pharmacologic characteristics, appear to have blood pressure-lowering activity in hypertensive patients. Comparisons between nonselective beta-blocking agents, such as propranolol and nadolol, with beta 1-selective drugs, such as metoprolol, atenolol and acebutolol, have demonstrated close similarities in their antihypertensive effects in patients. Similarly, beta blockers with and without intrinsic sympathomimetic activity (ISA) have comparable antihypertensive effects. However, beta-selective agents may offer some advantages over conventional beta blockers in hypertensive patients with concurrent conditions such as chronic obstructive airways disease, peripheral vascular disease, diabetes and hyperlipidemia. Beta 1-selective drugs are also preferred in diabetic patients receiving hypoglycemic agents because they do not interfere with glycogenolysis. Agents lacking ISA, such as propranolol, acutely increase peripheral resistance. beta blockers with ISA usually lower resistance. ISA may also minimize the bradycardia frequently found in elderly patients. Agents with ISA may protect against the decrease in high density lipoprotein cholesterol and the modest increase in triglycerides noted with some beta blockers that do not have ISA. Thus, in a large number of clinical situations in which hypertension is found, the properties of beta 1 selectivity and ISA allow beta blockers to be used with greater safety. Therefore, agents possessing both of these properties may be particularly valuable.
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PMID:Clinical significance of beta 1-selectivity and intrinsic sympathomimetic activity in a beta-adrenergic blocking drug. 288 76

There is good epidemiologic evidence that hypertension is associated with a high risk of cardiovascular disease. However, primary intervention trials have failed to demonstrate that a reduction in blood pressure in hypertensive patients reduces morbidity and mortality from cardiac events. Since various antihypertensive drugs adversely affect lipoprotein metabolism, these drugs may increase associated coronary risk and offset the beneficial effects of lowering blood pressure. This article reviews the effects of various antihypertensive drugs on plasma lipids, lipoproteins, and apolipoproteins. They can be summarized as follows: thiazide-type diuretics cause a marked elevation of plasma triglycerides and very low-density lipoprotein (VLDL) and minor increases in total cholesterol and low-density lipoprotein (LDL), but have little effects on high-density lipoprotein (HDL). The nonselective beta-blockers do not significantly affect total cholesterol and LDL, but increase total triglycerides and VLDL and decrease HDL. The changes in plasma lipids and lipoproteins caused by cardioselective beta-blockers and beta-blockers with intrinsic sympathomimetic activity are qualitatively similar but less pronounced. Calcium antagonists and angiotensin-converting enzyme inhibitors appear to have no significant effects on plasma lipids. alpha 1-Inhibitors reduce total triglycerides, total cholesterol, VLDL, and LDL and increase HDL. The possible mechanisms by which antihypertensive drugs affect cellular lipid metabolism (e.g., LDL receptor, lipid synthesis, lipoprotein lipase, lecithin cholesteryl acyltransferase, acylcholesteryl acyltransferase, and cholesteryl ester hydrolase) are described. The clinical significance of changes in blood lipids and cellular lipid metabolism caused by antihypertensive drugs is not yet totally clear. Nevertheless, before antihypertensive drug treatment is initiated, blood lipid levels should be measured to identify preexisting hyperlipidemia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of antihypertensives on plasma lipids and lipoprotein metabolism. 305 88

Hypertension, hyperlipidaemia and cigarette smoking are major risk factors in coronary heart disease. Since many antihypertensive drugs alter plasma lipid levels it is a subject of current discussion that these agents may increase associated coronary risk and therefore offset the beneficial effects of lowering blood pressure. The purpose of this paper is to review clinical and experimental data in the literature on the influence of data in the literature on the influence of antihypertensive drugs on lipid metabolism. The thiazides hydrochlorothiazide and chlorthalidone cause an elevation of plasma triglycerides and very low density lipoprotein (VLDL) but have little effect on total cholesterol, low density lipoprotein (LDL) and high density lipoprotein (HDL). The unspecific beta-blockers, e.g. propranolol, do not affect total cholesterol and LDL but increase total triglycerides and VLDL and decrease HDL. The changes of plasma lipids and lipoproteins caused by cardio-selective beta-blockers, e.g. atenolol and metoprolol, and unspecific beta-blockers with intrinsic sympathomimetic activity (ISA), e.g. oxprenolol and pindolol, appear to be qualitatively similar but less pronounced. The alpha 1-blocker prazosin reduces total triglycerides and slightly lowers total cholesterol. The concentration of VLDL plus LDL decreases while HDL may increase. Only very few studies have been reported on the effects of other antihypertensive drugs, e.g. clonidine, hydralazine, on plasma lipids. Several experimental studies reveal that antihypertensive agents exert direct effects on triglyceride and cholesterol metabolism. Although the pathophysiological mechanisms and the significance of the alterations of lipid metabolism induced by antihypertensive drugs are not yet clear, the following guidelines for the clinical use of these agents are recommended: (1) before initiating drug treatment in hypertensive patients, blood lipid levels should be measured to exclude a preexisting hyperlipidaemia, (2) during long-term therapy with antihypertensive agents, lipoprotein fractions should be controlled in order to reconsider the therapeutic regime if major alterations of blood lipid levels are observed.
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PMID:[Antihypertensive therapy and lipid metabolism]. 614 51

Heart rate, an important risk factor of coronary mortality, is highly correlated with numerous anthropometric and biochemical variables: height, body weight and hyperlipidemia; it varies, furthermore, with smoking and age and can be modified during pharmacotherapy for hypertension. From meta-analyses on different cardiovascular treatments, given after coronary events, only the efficacy of drugs significantly reducing heart rate is borne out (beta-blockers with sympathomimetic activity, or calcium-antagonists with a prevalent vasodilatory action do not provide a protective effect). Among calcium-antagonists, while the mechanism of action is similar at the cell level (delay of opening of voltage-operated slow channels), the distribution of activity within the vascular system varies markedly. Dihydropyridines (e.g., nifedipine) exert a dominant peripheral effect, with consequent vasodilation, whereas phenylalkylamines (verapamil) have both peripheral vasorelaxant and cardiac negative chronotropic activity, because of a reduced sinus node action potential. A relative tachycardia may occur with dihydropyridines, secondary to the activation of baroreceptors; the compensatory heart mechanism operated by verapamil antagonizes this reflex tachycardia. The activity of verapamil on the atrioventricular conduction allows both a slowing of functional recovery of the channel in hyperexcitable conditions (supraventricular tachycardia), and, moreover, increased diastolic intervals, with consequent improvement of coronary flow. New molecules can selectively reduce the sinus node activity without exerting other effects (hypotensive, anti-arrhythmic). From a comparative evaluation of these molecules with verapamil, it clearly emerges how this latter can provide a more acceptable pharmacodynamic profile, both for the hypotensive activity, and also for the control of reflex tachycardia, with a consequently improvement of coronary flow.
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PMID:[Pharmacological control of heart rate]. 785 54

A twenty-two-year-old male with no significant past medical history who presented with chest pain was found to have ST-segment elevation in leads II, III, aVF, and V4-V6. On subsequent EKGs, patient had new ST-segment elevations in anterolateral leads with dynamic changes. Cardiac catheterization showed acute dissection with thrombosis of the distal left main coronary artery leading into the ostial left anterior descending artery. The patient had no cardiac risk factors including hypertension, hyperlipidemia, diabetes, or family history of early cardiac disease. On further inquiry, the patient was found to be on two separate performance-enhancing supplements which contained synephrine, a sympathomimetic chemical which was later attributed as the cause of his acute coronary syndrome. Synephrine acts on alpha-1 adrenergic receptors causing peripheral and coronary vasoconstriction, hypertension, and hyperglycemia. Increased hemodynamic stress on the coronary arteries can lead to fatal dissections. Ours is an atypical case of synephrine-induced nonatherosclerotic spontaneous coronary artery dissection which helps caution the physicians about the importance of dietary supplement use in the history and possible side effects of such performance-enhancing additives.
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PMID:STEMI in a Young Male after Use of Synephrine-Containing Dietary Supplement. 2980 22