Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To examine the angiographic and hemodynamic determinants of dipyridamole-induced ST segment depression in patients with coronary artery disease, 41 patients with angiographically documented coronary disease who underwent dipyridamole-thallium-201 myocardial scintigraphy were studied. Dipyridamole-induced ST depression occurred in 14 (34%) of the 41 patients. Stepwise multivariate logistic regression was performed to compare the predictive value of angiographic findings (good coronary collateral vessels, jeopardized collateral vessels, multivessel disease), hemodynamic changes (changes in heart rate, systolic pressure, diastolic pressure and rate-pressure product), thallium-201 results (perfusion defect, thallium-201 redistribution) and demographic data (age, gender, medications). Only the presence of good coronary collateral vessels (p less than 0.02) and increases in rate-pressure product after dipyridamole infusion (p less than 0.02) were significant multivariate predictors of dipyridamole-induced ST depression. Good collateral vessels were more common in the group with ST depression (11 [79%] of 14) than they were in the group without ST depression (6 [22%] of 27; p less than 0.001). Rate-pressure product increased 2,835 +/- 1,648 beats/min.mm Hg in the group with ST depression compared with 1,179 +/- 1,417 beats/min.mm Hg in patients without ST depression (p less than 0.005). In conclusion, dipyridamole-induced ST segment depression in patients with coronary artery disease appears to be related to 1) the presence of good coronary collateral vessels, which may act by facilitating "coronary steal", and 2) increases in rate-pressure product, reflecting increased myocardial oxygen demand. These observations may explain the lack of prognostic value of dipyridamole-induced ST segment depression described in previous reports.
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PMID:Dipyridamole-induced ST segment depression during thallium-201 imaging in patients with coronary artery disease: angiographic and hemodynamic determinants. 337 18

An epidemiologic study of 1019 males, aged 45 to 59, included clinical and psychologic assessment, using Jenkins' questionnaire (JAS) and Freiburg personality identification questionnaire (FPI). Myocardial infarction survivors differed significantly from normal individuals by a number of psychological scores, such as depression, psychosomatic disturbances, anxiety, emotional lability. Anginal patients typically featured impulsiveness, psychosomatic disturbances, depression, anxiety, reserve, emotional lability. The examination of behavior determinants of arterial blood pressure in adolescents, based on cluster analysis, identified 3 groups of individuals with different behavioral syndromes. The clinical implication of these psychologic clusters was essential intercluster differences in terms of systolic and diastolic arterial blood pressure.
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PMID:[Behavior, personality and cardiovascular diseases]. 337 79

This study demonstrated the clinical significance of reverse redistribution, i.e., a decrease in the relative Tl activity in the redistribution image compared to that of the stress image after administration of dipyridamole. Dipyridamole was infused intravenously at a rate of 0.142 mg/kg per min for four min, and a stress image was obtained 10 min after the injection of two mCi 201Tl. Each patient returned for redistribution scanning in the identical position three hours after the isotope injection. The myocardial image of Tl was analyzed by single photon emission computed tomography and its washout rate was calculated by the segmental ROI method. Myocardial function and the motion of left ventricular wall were analyzed by 99mTc-RBC-gated cardiac pool imaging. The results were as follows: Reverse redistribution was noted in 27 (21.6%) of 125 consecutive Tl dipyridamole and redistribution myocardial imaging studies. The stress image demonstrated normal perfusion (group 1) and reduced perfusion (group 2) of Tl. Group 1 consisted of 17 patients with diabetes mellitus, supraventricular arrhythmias, hypertension, and others. Group 2 consisted of 10 patients with subendocardial infarction, diabetes mellitus, and hypertension, and others. The percentage prevalence of reverse redistribution among patients with supraventricular arrhythmia was 62.5% (five of eight patients), with subendocardial infarction 60.0% (three of five), with hypertension 42.8% (six of 14), and with diabetes mellitus 40.0% (eight of 20), while in those with transmyocardial infarction and angina pectoris no reverse redistribution percentage was found. The washout rate of Tl in normal perfusion areas was 44.0 +/- 12.8%, the reverse redistribution of group 1 was 47.4 +/- 12.8%, and of group 2 was 51.2 +/- 8.2%. The washout rate of the reverse redistribution of group 2 was significantly greater than that of the normal areas. In gated cardiac pool imaging, patients in group 2 had significantly larger areas showing abnormal contraction of the left ventricular wall and significantly lower ejection fraction than did group 1. In the electrocardiogram ST segment depression was noted more frequently in group 2 than group 1. No Q wave was present in the corresponding reverse redistribution area. These results suggest that reverse redistribution might occur in a region with a combination of scarred and normal myocardium, the metabolically affected myocardium, and an area with relatively increased myocardial blood flow. The patients in group 2 seem to have the more pathological myocardium than do those in group 1.
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PMID:[Reverse redistribution in dipyridamole-loading thallium-201 images using single photon emission computed tomography]. 349 7

The effects of orally administered indomethacin or placebo on coronary hemodynamics were studied in 23 patients with coronary artery disease. After indomethacin administration the systemic arterial pressure increased by 12 +/- 4% and the myocardial oxygen consumption by 24 +/- 11%. Coronary sinus flow did not change and coronary vascular resistance increased slightly. Oxygen saturation of the arterial blood did not change, but coronary sinus saturation decreased substantially. Hemodynamic values returned to normal 150 minutes after administration of indomethacin. During rapid atrial pacing, coronary sinus flow increased 79 +/- 14% above the rest value when pacing was done before indomethacin administration; only a 56 +/- 12% increase was seen when pacing was repeated after indomethacin. Peak heart rate achieved during atrial pacing, severity of angina and the degree of ST-segment depression were not altered by indomethacin treatment. Orally administered indomethacin has a mild coronary vasoconstrictive effect that does not interfere substantially with the expected increase in myocardial blood flow during rapid atrial pacing. Anginal threshold is not altered by orally administered indomethacin.
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PMID:Effects of indomethacin on coronary hemodynamics, myocardial metabolism and anginal threshold in coronary artery disease. 351 96

In 50 patients with chronic stable angina and in 10 asymptomatic young male volunteers, the behavior of S-wave amplitude was studied during episodes of ischemic ST-segment depression, both induced by exercise testing and occurring during ambulatory electrocardiographic monitoring. With exercise, all patients showed diagnostic ST-segment depression (0.16 +/- 0.05 mV) which, in 49, was associated with an increase in S-wave amplitude. No consistent changes in R-wave amplitude were observed. S-wave amplitude also increased in all control subjects during exercise, but the sum of R and S wave remained constant, while it increased in 42 patients. In the 10 study patients undergoing Holter monitoring we identified 170 episodes of ischemic ST-segment depression, of which 169 were associated with increased S-wave amplitude. Isolated increases in S-wave amplitude without ST-segment changes occurred in 3 of 4 normal subjects. Dipyridamole echocardiography revealed regional wall motion abnormalities in 12 of 21 patients; the changes were invariably associated with increased S-wave amplitude but not necessarily with diagnostic ST-segment depression. An increase in S-wave amplitude is almost invariably associated with subendocardial ischemia, sometimes in the absence of ST-segment changes; this sign could represent a sensitive (although less specific) additional marker of myocardial ischemia.
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PMID:Increase in S-wave amplitude during ischemic ST-segment depression in stable angina pectoris. 359 82

Nociceptive neurons in the dorsal horn of the cat spinal cord are depressed by vibration applied to the ipsilateral hind limb. The present study investigated the pharmacological properties of this depression because of the possibility that it represents the neural basis at the spinal level for the analgesic effects of vibration in humans. Experiments were done in cats anesthetized with sodium pentobarbital and acutely spinalized at the first lumbar level. Extracellular recordings were made from nociceptive neurons in the lower lumbar segments. The depression of these neurons induced by vibration to the hindlimb was attenuated by administration of the P1-purinergic (adenosine) receptor antagonist, caffeine (20-60 mg/kg i.v.); the maximum attenuation was 100%. Effects of caffeine began within 2 min after the start of injection (1-3 min injection period), were greatest in the 10 min period after the end of injection and lasted for up to 2 hr. Importantly, another P1-purinergic receptor antagonist, which does not cross the blood-brain barrier, 8-sulphophenyltheophylline (8-16 mg/kg), had no effect on the depression when given intravenously (n = 5); however, when administered by iontophoresis 8-sulphophenyltheophylline blocked the depression in 2 of 6 units. Dipyridamole (1.0-2.0 mg/kg i.v.), an inhibitor of adenosine uptake, potentiated the depression in 2 of 5 cases. These results prompt us to suggest that depression induced by vibration may be mediated by adenosine via the activation of P1-purinergic receptors. On the other hand, the GABAA antagonist, bicuculline, failed to attenuate vibration-induced depression when administered either intravenously (0.2-0.4 mg/kg; n = 5) or by iontophoresis (n = 10) and the glycine antagonist, strychnine (0.2-0.6 mg/kg; n = 3) and the opiate antagonist, naloxone (0.1-0.4 mg/kg; n = 4) were similarly ineffective. These findings suggest that vibration-induced depression of these units occurs without involvement of bicuculline-sensitive GABA receptors, strychnine-sensitive glycine receptors and naloxone-sensitive opiate receptors. In view of the fact that vibration-induced depression is evoked synaptically, this study is the first to demonstrate in the central nervous system a synaptic response which is mediated by adenosine. In addition, we suggest that the analgesic effects of vibration in humans may be mediated at the spinal level by activation of P1-purinergic receptors.
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PMID:Evidence that adenosine mediates the depression of spinal dorsal horn neurons induced by peripheral vibration in the cat. 367 Jun 2

To evaluate the usefulness in diagnosing coronary artery disease (CAD), dipyridamole-loading 201T1 myocardial scintigraphy was performed for 52 elderly patients (65-92 years, mean: 72 years), and the results were compared with data from the treadmill exercise tests. Thirty-five patients could not tolerate adequate exercise tests. Seven of them had reversible defects; six, fixed (irreversible) ones. Dipyridamole scintigraphy is therefore applicable in detecting CAD among patients with suspected CAD who are unable to perform adequate exercise tests. Four of 16 patients with positive exercise tests had no reversible defects; the exercise results in three were regarded as false positives. Seventeen patients experienced chest pain; 12 had ST depression during dipyridamole loading. There were no serious complications, but seven patients required aminophylline. We demonstrated previously that the sensitivity and specificity of dipyridamole scintigraphy in detecting CAD were 90% and 92%, respectively, in patients with chest pain undergoing coronary angiography. These results were superior to those of conventional exercise myocardial scintigraphy. Therefore, dipyridamole scintigraphy is regarded as a safe and useful method for detecting CAD, particularly in elderly patients who have ST and T wave abnormalities but cannot tolerate exercise test adequately.
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PMID:[Coronary artery disease detected noninvasively by dipyridamole-loading 201T1 myocardial scintigraphy in elderly patients]. 378 88

Nicardipine, 30 and 40 mg thrice daily, was administered to 66 patients with stable angina pectoris in a multicentre, randomised, double-blind, cross-over trial. With nicardipine therapy, duration of exercise and cumulative oxygen consumption increased, while times to onset of angina and 1 mm ST segment depression were prolonged. Anginal frequency and nitroglycerin consumption declined with use of nicardipine, but this did not reach statistical significance. Resting heart rate increased slightly and resting blood pressure decreased. Two patients on nicardipine and one on placebo sustained acute infarction. Otherwise, side effects were generally mild and transient.
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PMID:Nicardipine for stable angina pectoris. 392 58

This study assesses the clinical feasibility and usefulness of dipyridamole infusion for the detection of coronary artery disease (CAD) by using 2-dimensional echocardiography (2-D echo) and 12-lead electrocardiographic monitoring. Dipyridamole infusion (0.14 mg/kg/min for 4 minutes) was performed in 66 consecutive patients with effort chest pain and in 9 control subjects. Among the 28 patients with positive dipyridamole-echocardiography test responses, 18 had diagnostic electrocardiographic changes (ST-segment depression on anterolateral leads), but these changes were unrelated to the site of asynergy. The dipyridamole-echocardiography test had an overall sensitivity of 56% and specificity of 100% for the presence of CAD. Exercise stress testing (EST) had an overall sensitivity of 62% and a specificity of 80%. Thus, the dipyridamole-echocardiography test, which is feasible in essentially all patients with good basal echocardiograms, has a lower overall sensitivity in detecting CAD than EST but a higher specificity, detects the site of apparent ischemia as identified by regional asynergy more precisely than EST, and can unmask electrocardiographically silent effort ischemia.
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PMID:Dipyridamole-echocardiography test in effort angina pectoris. 403 26

Responses of the smooth muscle membrane of the rabbit bladder to intramuscular nerve stimulation were investigated by the micro-electrode and double sucrose-gap methods. The cell generated regular spontaneous action potentials. Acetylcholine produced a maintained increase in the frequency and ATP a transient increase. Noradrenaline only increased the frequency at very high concentrations. Application of short current pulses (50 microseconds) produced an initial excitatory junction potential (e.j.p.) with a superimposed spike, followed by a late depolarization. On some occasions, hyperpolarization of the membrane appeared between initial e.j.p. and the late depolarization. All these responses were abolished by tetrodotoxin. The late depolarization was enhanced by pre-treatment with neostigmine and abolished by atropine. This means that the delayed depolarization is due to activation of the muscarinic receptor. When the late depolarization was abolished, the amplitude of hyperpolarization was enhanced. The e.j.p. and contraction were unaffected by guanethidine, phentolamine, methysergide, mepyramine, quinidine or theophylline. This means that the e.j.p. is not mediated by activation of adrenergic, tryptaminergic, histaminergic or purinergic receptors. ATP reduced the amplitude of the e.j.p. due to depolarization of the membrane and reduction in the membrane resistance. The amplitude of the e.j.p. was gradually reduced by repetitive stimulation (0.5-2.0 Hz). However, the rate of depression was unchanged in the presence of ATP. Dipyridamole did not change the electrical and mechanical responses to field stimulation. These results do not support the proposal that ATP is the non-cholinergic excitatory transmitter. Apamine and tetraethylammonium (TEA) suppressed the hyperpolarization produced by field stimulation but guanethidine did not inhibit the hyperpolarization. Therefore, the hyperpolarization is due to increased K conductance of the membrane but it is not possible to conclude whether this component is due to the inhibitory action of a neurotransmitter or solely to after hyperpolarization of the spike. It was concluded that the rabbit bladder receives both cholinergic and noncholinergic excitatory neurones.
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PMID:Electrical and mechanical activity recorded from rabbit urinary bladder in response to nerve stimulation. 630 43


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