Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002962 (angina)
 21,142 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiographically normal coronary arteries are found in a substantial number of patients evaluated for angina pectoris. One third to one half of such patients demonstrate abnormalities of myocardial perfusion or metabolism when evaluated with invasive techniques. This study was designed to determine whether angina in such patients is attributable to abnormalities of perfusion at rest, maximal perfusion or vasodilator reserve and whether any identified abnormalities were global or regional in nature. Positron emission tomography was performed with oxygen-15-labeled water (H2(15)O) and oxygen-15-labeled carbon monoxide (C15O) before and after intravenous dipyridamole to assess regional myocardial perfusion and perfusion reserve in absolute terms in 16 normal subjects and 17 patients with chest pain and angiographically normal coronary arteries. Eight of the 17 patients had a myocardial perfusion reserve less than 2.5 (the lower limit of normal in studies with positron emission tomography, as well as with other techniques) and 9 of 17 patients had a normal response. In the patients with an impaired perfusion reserve, perfusion at rest was significantly higher than that measured in normal subjects (1.61 +/- 0.38 versus 1.25 +/- 0.28 ml/g per min, p less than 0.02) and maximal flow and perfusion reserve were significantly reduced (2.26 +/- 0.92 versus 4.62 +/- 1.58 ml/g per min and 1.4 +/- 0.5 versus 3.8 +/- 1.1, respectively; p less than 0.001 for both comparisons). Abnormalities of perfusion and perfusion reserve were spatially homogeneous without detectable regional disparities. Thus, nearly half of patients with chest pain and normal coronary arteries have abnormalities of myocardial perfusion that are detectable noninvasively with positron emission tomography and H2(15)O.
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PMID:Increased myocardial perfusion at rest and diminished perfusion reserve in patients with angina and angiographically normal coronary arteries. 238 32

Since beta-adrenoceptor blocking drugs were originally discovered and shown to be important therapeutic agents in the management of both angina pectoris and hypertension, many other similar drugs have become available. These share the common property of beta-adrenoceptor antagonism, though they may vary in terms of potency. However, they differ from one another in terms of their additional pharmacological properties--cardioselectivity, partial agonist activity, and membrane stabilizing activity. Cardioselectivity refers to the ability of some drugs, notably atenolol and metoprolol, to block beta 1 receptors without blocking beta 2 receptors. This has been considered to be of potential importance in patients with obstructive airways disease, patients with peripheral vascular disease, and patients with insulin-dependent diabetes during hypoglycemic crisis. Partial agonist activity is the intrinsic activity that some drugs have to stimulate the beta adrenoceptor while they are competitively antagonizing catecholamines. In consequence, they may have less effect on resting heart rate, cardiac output, peripheral vascular blood flow, and resting respiratory function. However, there is no good evidence that major adverse effects of beta-adrenoceptor blocking drugs such as congestive heart failure, bronchospasm, or symptoms of peripheral vascular disease are prevented by drugs with partial agonist activity: bradycardia may be improved, but its importance has probably been overemphasized. Membrane-stabilizing activity appears to be unimportant. As far as pharmacokinetic differences between drugs are concerned, lipid solubility is seen to be of increasing importance. The more water-soluble drugs have longer elimination half-lives, produce less interindividual variation in steady-state plasma concentrations, and penetrate the central nervous system less readily.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pharmacological characteristics of beta blockers and their role in clinical practice. 243 20

Calcium antagonists are a biochemically heterogeneous group of drugs that share the property of blocking the entry of calcium into cells by voltage-operated channels in cardiac and smooth muscle. They are useful in the management of angina pectoris and hypertension. The drugs available at present include nifedipine, verapamil, and diltiazem. All three drugs have similar pharmacokinetic properties of low and variable bioavailability, high first-pass metabolism, short elimination half-life, and active metabolites. The pharmacokinetics of calcium antagonists are relevant, because in individual patients the intensity and duration of the pharmacological effect is related to the level of drug in plasma. Amlodipine is a new dihydropyridine calcium antagonist in advanced clinical development. It has a completely different pharmacokinetic profile. It is water soluble and photostable, and has a long half-life of 35-50 h. Amlodipine is slowly absorbed, its absolute bioavailability is high, and it is extensively metabolized in the liver. The long half-life is associated with a prolonged (greater than 24 h) duration of pharmacodynamic action. Amlodipine, because of its novel pharmacokinetics, may offer practical advantages over existing calcium antagonists in the long-term treatment of cardiovascular disease.
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PMID:Pharmacokinetics of calcium antagonists. 246 22

Bisoprolol is a new highly beta 1-selective beta-adrenoceptor blocking drug; it is devoid of intrinsic sympathomimetic effects. Its haemodynamic effects are those expected from beta 1-blockade, heart rate is reduced at rest and on exercise, cardiac output falls and peripherial resistance is increased. Consequent on the beta 1-selectivity there is much greater inhibition of exercise tachycardia compared to inhibition of isoprenaline-induced falls of diastolic blood pressure, in contrast to propranolol. Studies in asthmatics confirm the selectivity of bisoprolol. Bisoprolol has similar solubility in water and organic solvents and predictably therefore about half is excreted by the kidneys unchanged, half metabolized by the liver. Estimates of half-life average about 10-12 h, this is in accord with the therapeutic efficacy of once daily administration. Therapeutic studies have demonstrated the efficacy of bisoprolol in angina pectoris, arrhythmias and hypertension. Comparative studies against atenolol and verapamil in angina suggest similar efficacy. In hypertension a similar antihypertensive effect to nifedipine has been found, while a significantly greater lowering of blood pressure was seen than that obtained with a diuretic. Some studies have also suggested more consistent antihypertensive effect from bisoprolol than atenolol 24 h after administration. This may have been a dosage phenomenon or reflects the longer plasma elimination half-life of bisoprolol, and requires confirmation. Bisoprolol has a favourable side-effect profile.
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PMID:Bisoprolol: a new beta-adrenoceptor blocking drug. 289 95

PN 200-110 (isradipine) is a new dihydropyridine calcium antagonist with selective actions on the heart as well as the peripheral circulation. It selectively inhibits the sinus node but not atrioventricular conduction and its negative inotropic action is minimal, about 20 times weaker than its negative chronotropic effect. This in vitro pattern also expresses itself in vivo: partial suppression of the reflex tachycardia induced by its peripheral vasodilatation and no effect on the P-Q interval on the electrocardiogram even at large doses. The presence of first- or second-degree heart block should therefore not limit its use, whereas the sick sinus syndrome might. PN 200-110 does not decrease myocardial contractile force even in vagotomized animals with full beta blockade. PN 200-110 nevertheless lowers myocardial oxygen consumption mainly by its action on afterload. It should therefore be useful in angina pectoris. PN 200-110 is a powerful peripheral vasodilator. It preferentially dilates coronary, cerebral and skeletal muscle vasculature. Its long lasting (24 to 48 hours) antihypertensive action is not accompanied by tachycardia in spontaneously hypertensive rats and it enhances sodium and water excretion in normotensive rats. It should be useful in the treatment of hypertension, and, considering its pattern of cardiac actions, perhaps also as an after-load-reducing agent for the treatment of heart failure. Antiarteriosclerotic effects in conscious rabbits were found at reasonably small doses, suggesting that such effects might occur in man at therapeutic doses.
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PMID:Selective effects of PN 200-110 (isradipine) on the peripheral circulation and the heart. 294 86

The clinical use of calcium antagonist drugs in coronary artery disease preceded knowledge of the mechanism of their action. Basic research into their pharmacological actions and development of a wide range of compounds which block calcium entry into cells enabled clinicians to greatly expand the indications for their use. Thus the calcium antagonists were rediscovered and found to be potent anti-anginal drugs when used in adequate dosage for effort related angina. Knowledge of their potent relaxing action on vascular smooth muscle led to their use in coronary artery spasm. The exact trigger mechanism/s for spasm and the reason for enhanced vascular reactivity remain unclear, perhaps explaining the failure of specific antagonist therapy. Calcium antagonists acting nonspecifically inhibit both induced and spontaneous attacks of vasospastic angina. They may favourably influence the prognosis and are now drugs of first choice for this condition. The vasodilator action of these drugs has most recently been utilized to treat hypertension, with efficacy confirmed in many controlled trials. Unlike other vasodilators, the calcium antagonists reduce blood pressure without salt and water retention, and with mild or no stimulation of renin, aldosterone, or sympathetic nervous overactivity, and without postural effects. This spectrum of action makes them ideal therapeutic agents, and current guidelines are changing to include calcium antagonists as first or second line therapy.
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PMID:Calcium antagonist drugs in the treatment of coronary spasm, effort angina and hypertension. 330 67

We determined the myocardial metabolic rate for glucose (MMRGlc) in the ischemic or infarcted myocardium using 18-F-fluorodeoxyglucose (18-FDG) with positron emission tomography (PET), and studied energy metabolism in the ischemic myocardium. In some cases, we compared glucose metabolism images by 18-FDG with myocardial blood flow images using 15-oxygen water. Two normal subjects, seven patients with myocardial infarction and four patients with angina pectoris were studied. Coronary angiography was performed within two weeks before or after the PET study to detect ischemic areas. PET studies were performed for patients who did not eat for 5 to 6 hours after breakfast. Cannulation was performed in the pedal artery to measure free fatty acid, blood sugar, and insulin. After recording the transmission scan for subsequent correction of photon attenuation, blood pool images were recorded for two min. after the inhalation of carbon monoxide (oxygen-15) which labeled the red blood cells in vivo. After 20 min., oxygen-15 water (15 to 20 mCi) was injected for dynamic scans, and flow images were obtained. Thirty min. after this procedure, 18-FDG (5 to 6 mCi) was injected, and 60 min later, a static scan was performed and glucose metabolism images were obtained. Arterial blood sampling for the time activity curve of the tracer was performed at the same time. According to the method of Phelps et al, MMRGlc was calculated in each of the region of interest (ROI) which was located in the left ventricular wall. MMRGlc obtained from each ROI was 0 to 17 mg/100 ml/min. In normal subjects MMRGlc was 0.4 to 7.3 mg/100 ml/min.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Glucose metabolism in ischemic myocardium: quantitative imaging using positron emission tomography]. 349 6

Twenty-four patients with stable angina pectoris were studied after aortocoronary bypass surgery with hypothermic cardiopulmonary bypass (CPB). Twelve patients (radiant heat supply group) were rewarmed during CPB to a nasopharyngeal temperature of at least 38 degrees C and a mean rectal temperature of 34.4 degrees C. Postoperatively they received radiant heat supply from a thermal ceiling. In addition, a heating water mattress was used during the end of the operation and heated, humidified inspired gases were administered intra- and postoperatively. The other 12 patients (combination heat supply group) had the rewarming during CPB extended until the rectal temperature exceeded 36 degrees C, but otherwise received the same treatment as the radiant heat supply group. The combination of extended rewarming during CPB and postoperative radiant heat supply significantly reduced oxygen uptake, carbon dioxide production and the required ventilation volumes during early recovery as compared with the values in the radiant heat supply group. The reduced metabolic demands were accompanied by lower cardiac index and oxygen delivery, which, however, were sufficient for adequate tissue perfusion as judged by the similarity in oxygen extraction and arterial base excess values in the two groups. The metabolic demands and ventilatory requirements were reduced to a level at which safe early extubation is possible.
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PMID:Postoperative ventilatory and circulatory effects of heating after aortocoronary bypass surgery. Extended rewarming during cardiopulmonary bypass and postoperative radiant heat supply. 349 81

This study was performed to measure regional myocardial blood flow (MBF) quantitatively using dynamic positron emission tomography (PET) and O-15 water. The subjects consisted of two normal volunteers, four patients with normal coronary angiograms (CAG), two patients with angina pectoris (3-vessel disease) and three patients with myocardial infarction. O-15 water (15-20 mCi) was injected via the cubital vein in a bolus, and dynamic PET was performed. MBF was calculated according to the method of Iida. The region of interest (ROI) was selected on the left ventricular wall (septum, anterior and lateral walls) and MBF was calculated in each ROI. In normal volunteers, MBF was 1.07 to 1.17 ml/g/min. It was 0.96 to 1.02 ml/g/min in patients with normal CAG, and 0.53 to 0.64 ml/g/min in patients with angina pectoris in the ischemic area. In patients with myocardial infarction, MBF was so diminished in the infarcted area as detected by 2-DE or ECG that the absolute value was almost 0 ml/g/min. In patients with angina pectoris, there was no definite defect on the MBF image, but we could estimate the severity of coronary stenosis by quantifying the MBF. The clinical advantages of this method include estimation of the severity of coronary arterial stenosis in the resting state.
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PMID:[Regional myocardial blood flow quantitatively measured using O-15 water and dynamic positron emission tomography]. 350 32

Chemicals have become indispensible for the maintenance of health in animals and man. The route of administration of each medicament is decided by factors such as site of desired action, chemistry of the active ingredient, age and species of the patient, and frequency of administration (or desired duration of activity). In situations where the oral and hypodermic routes, which are used most frequently, are inadequate or unsatisfactory, dermal application can provide a valuable alternative method to achieve systemic activity. Examples of formulations currently available for dermal application contain diverse chemicals and are intended for a variety of purposes, such as crufomate against cattle grubs, fenthion against cattle lice, levamisole against gastrointestinal nematodes, nitroglycerine for angina pectoris, and scopolamine for motion sickness. The skin acts as a barrier to penetration by chemicals and micro-organisms by virtue of its morphology and chemical composition. Chemicals which do penetrate, do not necessarily pass through the appendages (hair follicles and gland ducts), but mostly penetrate through the interjacent epidermis, either through the cells, or via the intracellular spaces. These spaces have recently been shown by electron microscopy to be filled by an amorphous substance which exudes on the skin surface in convex ridges. This substance has a lipid nature, but is not hydrophobic as is often accepted. For a chemical to be able to penetrate the skin, it must be partially water and lipid soluble, polar, and weakly ionizing. A variety of factors can possibly affect the permeability of skin for a chemical. These include species differences in morphology (skin thickness, tightness of intercellular junctions, density of hair follicles and other appendages), biochemistry, and physiology; seasonal and climatic variations; and differences between breeds and genders. Species differences in skin permeability are largely unpredictable and inconsistent. An observed difference between two species for one chemical cannot necessarily be extrapolated to another.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Cutaneous absorption of chemicals]. 354 56


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