The authors studied ED50 of bethanechol on the contractilities of the smooth muscles isolated from various organs of rat under the presence of atropine (a classical competitive blocker of cholinergic muscarinic receptor) or minaprine (a newly developed antidepressant drug) to investigate the peripheral anticholinergic effect of minaprine. The results were as follow: 1) There was no significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine 10⁻⁸M and 10⁻⁷M in the smooth muscles isolated from the duodenum. 2) There was no significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine 10⁻⁸M and 10⁻⁷M in the smooth muscles isolated from the ascending colon. 3) There was significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine 10⁻⁸M and 10⁻⁷M in the smooth muscles isolated from the urinary bladder (P<0.01) 4) There was significant difference between ED50 of the atropine 10⁻⁸ and minaprine (10⁻⁸M) in the smooth muscles isolated from the urinary bladder (P<0.05).
Animals ; Atropine ; Bethanechol ; Colon, Ascending ; Duodenum ; Muscle, Smooth ; Rats ; Urinary Bladder

The force-interval relationship of cardiac muscle has been known as not only a fundamental manifestation of beat-to-beat kinetics of intracellular activator calcium which control contractile response but also a potential clinical tool for evaluating cardiac contracile function. In this study were evaluated the force-interval relationship of intact canine left ventricle through mechanical restitution curves by plotting contrctile responses to varying steady state, extrasystolic and postextrasystolic intervals, and compared the force-interval relationships of intact canine left and right ventricles quantitatively. Effects of localized myocardial ischemia on the left ventricular force-interval relationship and relaxtion function were also evaluated 30 minutes after ligating proximal left anterior descending coronary artery through observing contractile and relaxtion responses to various intervals. 1) Mechanical restitution curve of left ventricle showed that left ventricular dp/dt max responses rose stiffly until plateau level with increasing postextrasystolic intervals, then declined with further increment of postextrasystolic intervals. 2) Mechanical restitution curve of left ventricle shifted leftward and upward with shortening of steady state and extrasystolic intervals, which suggest intracellular calcium kinetics during electrical diastole may operate as a mechanism of the force-interval relationship. 3) Steady state contractile responses remained unchanged but maximal contractile responses increased significantly or contractile reserve in intact left ventricle. 4) Normalized force-interval relationships of left and right ventricle were similar quantitatively, which suggest the force-interval relationship is independent of structural factors in intact canine heart. 5) Occlusion of coronary artery lowered absolute values of left ventricular dp/dt max responses to varying postextrasystolic intervals, but didn't show significant changes of normalized dp/dt max responses, which suggest force-interval relationship be also present in spite of localized myocardial ischemia. 6) Responses of normalized left ventricular dp/dt min to varying postextrasystolic intervals were similar to those of normalized dp/dt max but reduced after coronary artery occlusion in the range above 100% dp/dt max response, which may be used for the detection and evaluation of deranged myocardial relaxation in the left ventricle with localized myocardial ischemia.
Calcium ; Coronary Vessels ; Diastole ; Heart ; Heart Ventricles ; Kinetics ; Myocardial Ischemia ; Myocardium ; Relaxation ; Ventricular Function, Left*

The activity of Mg++-dependent, Ca++-activated adenosine triphosphatase (Ca-ATPase) of rat liver mitochondria was studied at varying medium compositions, pH and temperatures. The enzyme system was characteristically sensitive to Ca++ concentration with a KmCa of approximately 0.06 mM. The optimal concentration of Mg was about l mM, above which the enzyme activity was progressively inhibited. The inhibitory effect of high Mg++ concentrations appeared to be due to the alteration of the Mg++/ATP ratio. Variations in the Mg++/ATP ratio affected Vmax but not the KmATP. The pH optimum for enzyme activity increased as the incubation temperature decreased, but the optimal OH-/H+ ratio of the medium was constant at around 0.1, regardless of temperature. The activity of the enzyme was not affected by La# (0.01-1 mM) and Ruthenium red (2.5-10.0 microM). These results indicate that 1) the enzymatic characteristics of the Ca-ATPase system in the rat liver mitochondria is typical of those from other tissue preparations, 2) the enzyme system maintains the most effective catalytic conformation at a fixed level of OH-/H+ ratio of 0.1 when the temperature changes, and 3) the enzyme system may not play a role in the physiological transport of Ca++ in mitochondria.
Animal ; Ca(2+)-Transporting ATPase/metabolism* ; Calcium/pharmacology ; Enzyme Activation/drug effects ; Female ; Hydrogen-Ion Concentration ; Magnesium/pharmacology ; Male ; Mitochondria, Liver/enzymology* ; Rats ; Temperature

To assess the diagnostic value of low level predischarge exercise test in the prediction of multivessel disease and left ventricular abnormality rate limited treadmill test, coronary arteriography and left ventriculography were admitted to the coronary care unit at Seoul National University Hospital from February 1985 to April 1986. The following results were obtained; 1) During and immediately after the treadmill test, ischemic ST segment depression were observed in 7 patients (20.6%). On subsequent coronary arteriography, 6 of them were found to have multivessel coronary artery disease. The sensitivity of ST segment depression in prediction of multivessel disease was 31.6%, the specificity was 93.3% and prediction value was 85.7%. 2) In 11 patients (32.3%), the exercise test were discontinued because of anginal pain, fatigue, or dyspnea. The sensitivity of above symptoms in prediction of multivessel disease was 47.4%, the specificity was 86.7% and prediction value was 81.8%. 3) The sensitivity of ST segment depression and/or symptom in prediction of multivessel disease was 68.4%, the specificity was 80%, and the prediction value was 81.25%. 4) The ST segment elevation were observed in 10 patients (29.4%). The sensitivity of ST segment elevation in prediction of complicated left ventricular aneurysm was 58.3%, the specificity was 87.5%, and the prediction value was 70%. 5) No serious complication developed by the treadmill test. It is concluded from above results that low level predischarge treadmill exercise test is useful and safe test in the prediction of multivessel disease and left ventricular aneurysm in patients with recent acute myocardial infarction.
Aneurysm ; Angiography ; Coronary Artery Disease ; Coronary Care Units ; Depression ; Dyspnea ; Exercise Test* ; Fatigue ; Humans ; Myocardial Infarction* ; Sensitivity and Specificity ; Seoul

The coronary arteriography and left ventriculography were performed on 63 patients with acute myocardial infarction who were admitted to coronary care unit of Seoul National University Hospital from September 1984 to October 1986 within 30 days after onset of acute myocardial infarction (median: 16 days) to delineate the extent of coronary artery disease and the left ventricular function. The results were as follows; 1) The ratio of male to female was 59:4 (14.75:1) and 34.9% of all patients were at their 6th decade. 2) The infarction were transmural in 58 patients (92.1%) and nontransmural in 5 patients (7.9%). Among 58 patients with transmural infarction, 33 (56.9%) had anterior wall infarction, 15 (25.9%) had inferior wall infarction and 10 (17.2%) had anteroinferior wall infarction. 3) Among 63 patients, 4 (6.3%) showed completely normal coronary artery on coronary arteriography and 3 (4.8%) had insignificant stenosis (lesser than 50%) reduction in luminal diameter). The 39.7% of all patients had one-vessel disease, 27% two-vessel disease and 22.2% three-vessel disease. 4) Among 58 patients with transmural infarction, 31 (53.4%) showed complete occlusion of infarct related artery. And 73.4% of the patients with inferior wall infarction showed complete occlusion of infarct related artery. None of the patients with non-transmural infarction had complete occlusion. 5) In 21 patients who had the coronary arteriography within 14 days after the onset, 12 (57.2%) showed complete occlusion of infarct related artery and among 42 patients who were studied 15-30 days after the onset, 19(45.2%) showed complete occlusion. 6) Nineteen patients (30.2%) were found to have left ventricular aneurysm. 7) The left ventricular ejection fraction were significantly higher in the patients with non-transmural infarction than in patients with transmural infarction. The difference in left ventricular ejection fraction between the patients with anterior infarction and with inferior infarction, between single vessel disease and multiple vessel disease were not significant. 8) The older age group showed a tendency to have higher prevalence of multivessel disease. 9) As complication of coronary arteriography and left ventriculography, one episode of ventricular fibrillation was observed without mortality. From the above results of this study, it is concluded that coronary arteriography and left ventriculography can be safely performed within 30 days after the onset of acute myocardial infarction: A significant number of patients had normal or minimally diseased coronary artery: more than half of the patients with transmural infarction had complete occlusion of infarct related artery: the patients with nontransmural infarction had better left ventricular function than with transmural infarction.
Aneurysm ; Angiography ; Arteries ; Constriction, Pathologic ; Coronary Artery Disease ; Coronary Care Units ; Coronary Vessels ; Female ; Humans ; Infarction ; Male ; Mortality ; Myocardial Infarction* ; Phenobarbital ; Prevalence ; Seoul ; Stroke Volume ; Ventricular Fibrillation ; Ventricular Function, Left

BACKGROUND: C-type natriuretic peptide (CNP), secreted from endothelial cells, dilates the vessel and increases the renal excretion of sodium and water. Plasma CNP level is not elevated in patients with congestive heart failure (CHF), but the myocardial content of CNP is increased, suggesting paracrine or autocrine role of CNP. We studied to compare the effect of ANP and CNP on vasorelaxation in CHF rat model. METHODS: Coronary artery ligation was performed in Sprague Dawley rats, resulting in CHF (n=5) and they were fed with ordinary chow for 10 weeks. After measuring hemodynamics, aorta and pulmonary artery were incised and studied in organ chamber to measure the isotonic force to KCl and to observe the relaxation response to atrial natriuretic peptide (ANP), and CNP in vessels precontracted with phenylephrine. Normal Sprague Dawley rats (n=5) were used as control. RESULTS: There were no difference in vasorelaxation responses to ANP between control and CHF rats. The response to CNP was significantly impaired in both aorta and pulmonary artery of CHF rats compared to control rats.
Animals ; Aorta* ; Atrial Natriuretic Factor ; Coronary Vessels ; Endothelial Cells ; Estrogens, Conjugated (USP)* ; Heart Failure* ; Hemodynamics ; Humans ; Ligation ; Models, Animal ; Myocardial Infarction ; Natriuretic Peptide, C-Type* ; Natriuretic Peptides ; Phenylephrine ; Plasma ; Pulmonary Artery* ; Rats* ; Rats, Sprague-Dawley ; Relaxation* ; Sodium ; Vasodilation

BACKGROUND: It is well known that hypertension attenuate endothelium-dependent vasodilator response. And this finding is closely related to the development of atherosclerosis. Recently it is reported that the expression of NADPH-dependent oxidase is increased in angiotensin-induced hypertension model and superoxide (O2) produced from that might contribute to the development of vascular diseases. The possible mechanism is the degradation of endothelium-derived NO by O2. We hypothesized that SOD prevents endothelial dysfunction via prevention of the degradation of endothelium-derived NO. METHODS AND MATERIALS: We made renovascular hypertension model by constricting abdominal aorta just above the left renal artery of Sprague-Dawley female rats. The descending thoracic aorta was stuied in the organ chambers using acetylcholine as an endothelium-dependent vasodilator with or without pretreatment of SOD. RESULTS: Blood pressures of all 14 rats were significantly increased (174/123 mmHg, mean 146 mmHg). The residual tensions of the vessels precontracted by phenylephrine were similar in both groups (15.04+/-19.53 % in SOD group vs 11.84+/-18.57% in non-SOD group, p=.66). CONCLUSIONS: The endothelial dysfunctions in the rat aorta with renovascular hypertension were not improved by SOD. There is no acute effect of SOD on endothelial function in high renin/angiotensin state.
Acetylcholine ; Animals ; Aorta* ; Aorta, Abdominal ; Aorta, Thoracic ; Atherosclerosis ; Endothelium ; Female ; Humans ; Hypertension ; Hypertension, Renovascular* ; Oxidoreductases ; Phenylephrine ; Rats* ; Rats, Sprague-Dawley ; Renal Artery ; Superoxides ; Vascular Diseases

No abstract available.
Cholera* ; Korea*

OBJECTIVES: Anhedonia, defined as an inability to experience pleasure, has been considered to be a core feature of schizophrenia and depression. The purpose of the present study was to compare the specific characteristics of anhedonia in patients with the two illnesses by examining hedonic capacity during phased hedonic experience. METHODS: Hedonic rating tasks, using the film clips of physical and social hedonic stimuli and neutral stimuli, were performed by 29 patients with schizophrenia, 20 patients with depression, and 29 normal controls. Each task consisted of 'preview phase' with insufficient emotional information, and a subsequent 'theme phase' with sufficient emotional information. RESULTS: In normal controls, the mean hedonic score was increased in the theme phase compared with the preview phase, suggesting an appropriate augmentation of the hedonic response. In patients with schizophrenia, hedonic scores in the preview phase were comparable with those in normal controls, but showed deficient augmentation in the theme phase. In patients with depressive disorder, the range of increments in scores between the preview and theme phases was normal, but the scores themselves were lower in both phases than in the other two groups. CONCLUSION: The results indicate that patients with schizophrenia show a deficient augmentation of the hedonic response, whereas patients with depressive disorder have a pervasive lack of hedonic capacity.
Anhedonia ; Depression ; Depressive Disorder ; Humans ; Pleasure ; Schizophrenia

BACKGROUND: To evaluvate the hypothesis that reperfusion injury and reperfusion arrhythmia could be caused by oxyzen free redicals and that prolonged myocardial dysfunction could be induced by oxyzen free redical. METHODS: Experimnetal model of anesthetized open chest dogs was used. Coronary artery was occluded for 60 minutes and reperfusion was performed 4 hours. In 5 dogs, superoxide dismutase and catalase were infused concomitantly 15 minutes after coronary occlusion to 15 minutes after reperfusion. In 9 dogs, 0.9% saline was infused instead of free redical scavengers. Hemodynamic parameters such as heart rate, left ventricular peak systolic pressure, end-diastolic pressure, peak positive dP/dt, and peak negative dP/dt were analysed. Infarct size was estimated by the unstained area in nitroblue tetrazolium staining and risk area was calculated from the unstained area after methylen blue infusion. Regional systolic function was observed in systolic thickening of ischemic area by echocardiogram. RESULTS: 1) Reperfusion arrhythmia occurred in 67% of control group and in 50% of drug treated group. 2) Systolic hemodynamic parameters such as peak systolic pressure, peak positive dP/dt showed no difference between control and drug-treated group. 3) Diastolic parameters such as end-diastolic pressure and peak negative dP/dt were not different in two groups. 4) Regional systolic parameter measured by systolic thickening in ischemic area improved after reperfusion and continued to be better in drug treated group than in control group. 5) Infarct size, risk area, ratio of infarct size to risk aera were not different in two groups. CONCLUSION: Superoxide dismutase and catalase showed no effect in reducing the infarct size in anesthetized open chest canine model with 60 minutes of coronary occlusion 4 hours of reperfusion. However, postischemic prolonged myocardial dysfunction tended of improve-after reperfusion in drug treated group.
Animals ; Arrhythmias, Cardiac ; Blood Pressure ; Catalase* ; Coronary Occlusion ; Coronary Vessels ; Dogs ; Heart Rate ; Hemodynamics ; Myocardial Infarction* ; Necrosis* ; Nitroblue Tetrazolium ; Reperfusion ; Reperfusion Injury ; Superoxide Dismutase* ; Superoxides* ; Thorax