Publications by authors named "TAKEMURA G"

To elucidate the pathophysiological role of the hydroxyl radical (.OH) during the postischemic reperfusion of the heart, we measured the .OH product in the coronary effluent from isolated perfused rat heart during a 30-minute reperfusion period after various ischemic intervals of 5, 10, 15, 20, 30, and 60 minutes.

View Article and Find Full Text PDF

To elucidate the significance of hydroxyl radical (.OH) in postischemic reperfusion injury, we measured the .OH production in the coronary effluent collected from isolated perfused rat hearts during reperfusion period of 15 minutes after various ischemic intervals ranging from 5 to 60 minutes.

View Article and Find Full Text PDF

Failure to Reduce Infarct Size by Intracoronary Infusion of Recombinant Human Superoxide Dismutase at Reperfusion in the Porcine Heart: Immunohistochemical and Histological Analysis. Journal of Molecular and Cellular Cardiology (1991) 23, 1287-1296. We quantitatively determined the extent of infarction and contraction band necrosis in porcine hearts, and analyzed the distribution of administered recombinant human superoxide dismutase (h-SOD) in the myocardium using a polyclonal antibody to h-SOD.

View Article and Find Full Text PDF

The time course of hypertrophy of surviving myocytes overlying the infarct after the onset was examined and the hypertrophy was analyzed in relation to the transmural extent of infarct in 34 autopsied hearts with Q wave infarction. The 34 hearts were divided into 4 groups according to the length of time between the onset of infarction and death. This was less than 5 days in group 1 (n = 10), 20-30 days in group 2 (n = 7), 40-60 days in group 3 (n = 7), and 12-24 months in group 4 (n = 10).

View Article and Find Full Text PDF

To investigate the mechanism of cardiac dysfunction in myocarditis, myoglobin, an intracellular oxygen-transport, was immunohistochemically examined in biopsy specimens obtained from the right side of the ventricular septum and left ventricular free wall in 58 patients with myocarditis and 19 controls. Sections 4 microns thick were stained by the indirect immunoperoxidase method using a polyclonal antibody to human myoglobin as the primary antibody. Under light microscopy, the intensity of myoglobin immunoreactivity in the tissue section was semiquantitatively classified from grade 0 to grade 3.

View Article and Find Full Text PDF

To investigate the ventricular expression of atrial natriuretic polypeptide (ANP) in human hypertrophic heart, we conducted an immunohistochemical study using endomyocardial biopsy specimens obtained from the right side of the interventricular septum (RVB), left ventricular free wall (LVB), or both of 39 patients with hypertrophic cardiomyopathy (HCM), and 9 control subjects without hypertrophy. No HCM patients had apparent congestive heart failure. ANP was not present in control subjects' RVB or LVB specimens, but was found in HCM patients', showing its characteristic distribution patterns (RVB > LVB, p < 0.

View Article and Find Full Text PDF

To investigate the ventricular expression of atrial natriuretic peptide (ANP) in human hypertrophic hearts, we conducted an immunohistochemical study of 130 endomyocardial biopsy specimens obtained from the right side of the ventricular septum (RVB), left ventricular free wall (LVB), or both from a total of 80 patients: 44 patients with hypertrophic cardiomyopathy (HCM), 14 with apical hypertrophic cardiomyopathy (APH), 13 with hypertensive hearts (HHD), and nine without hypertrophy (controls). No patients had apparent congestive heart failure. ANP was not seen in ventricular myocytes in controls but was identified in biopsy specimens of hypertrophic hearts, and its distribution was characteristic in each hypertrophic group: 15 RVB (37%) and two LVB (7%) of the HCM group, one RVB (7%) and two LVB (18%) of the APH group, and zero RVB (0%) and five LVB (46%) of the HHD group.

View Article and Find Full Text PDF

Study Objective: Protective effects of nipradilol, a newly synthesised vasodilating beta adrenoceptor antagonist, isosorbide dinitrate, and bunazosin on coronary artery constriction induced by intracoronary injection of acetylcholine were determined by coronary arteriography and compared in vivo in pigs.

Design: Acetylcholine (12.5, 25, 50, 100 and 200 micrograms) was given into the right coronary artery under left ventricular pacing to maintain constant systemic haemodynamics.

View Article and Find Full Text PDF

We studied the expression and distribution of atrial natriuretic polypeptide in the ventricles of 27 autopsied children with Kawasaki disease. Fourteen of the children had died in the acute stage of the disease. Three without any coronary artery aneurysms died due to myocarditis, while 11 with coronary artery aneurysms also had myocarditis but died of coronary heart disease.

View Article and Find Full Text PDF

The expression of atrial natriuretic polypeptide (ANP) in the ventricles of human hearts with myocardial infarction (MI) was studied immunohistochemically. Immunoreactive myocytes were identified in the ventricular tissues of all of 16 hearts with old MI (both with and without heart failure) and in all five hearts with subacute MI, but not in any of the eight hearts without MI nor in the five with acute MI. In the nonfailing hearts with MI, ANP positive myocytes surrounded the areas of infarction, and were also seen in the subendocardium of the infarcted segment.

View Article and Find Full Text PDF

We report a case of left atrial myxoma found when examination was made for the cause of orthostatic hypotension. The case was that of a man of 61 years of age. For the previous 2 years, the man had felt dizzy only at the standing or sitting position.

View Article and Find Full Text PDF

In order to clarify the pathogenesis of acute myocardial infarction (MI) in hearts with normal coronary arteries, infarct size, and the extent of contraction band necrosis (CBN), coagulation necrosis, and hemorrhage were quantitatively examined using an image analyzer in 5 autopsy cases of MI with normal or nearly normal extracardiac coronary arteries. One patient died 40 h after acute MI. A second patient with acute MI due to severe spasm of segment 6, confirmed by cineangiography, died three days later.

View Article and Find Full Text PDF

With coronary arteriography we examined the effect of acetylcholine (ACh) on large and small coronary arteries. ACh (12.5 to 200 micrograms) was injected into the right coronary arteries of 10 pigs during left ventricular pacing.

View Article and Find Full Text PDF

To determine whether or not male (NZWXBXSB)F1 [WXB)F1) mice exhibiting a lupus-like syndrome died of acute myocardial infarction (MI), and whether acute MI is directly related to small coronary artery disease, acute and old MIs were examined histologically in 55 dead (WXB)F1 male mice and 30 age-matched, surviving (WXB)F1 male mice used as a control group. In each heart from the 15 dead mice with MI and the five surviving mice without MI, 300 to 400 5-microns-thick serial sections were made; every fourth section was stained. Acute MI was found in 35 (64%) dead mice and in one (3%) survivors, whereas old MI was found in 50 (91%) dead mice and 17 (57%) survivors: a significant difference between the dead and surviving mice.

View Article and Find Full Text PDF

To investigate the mechanism of expression of atrial natriuretic polypeptide (ANP) in human ventricles, we conducted an immunohistochemical study of ANP in biventricular endomyocardial biopsy specimens obtained from a total of 49 patients with cardiac dilatation due to dilated cardiomyopathy (21 patients), postmyocarditis (18 patients), or volume overload (five patients) and subjects with no dilatation as controls (five patients). Four-micron thick sections were stained by an indirect immunoperoxidase method using monoclonal antibody to alpha-human ANP as the primary antibody. The frequency of ANP-present myocytes was calculated in each specimen and compared with clinical, echocardiographic, hemodynamic, angiographic, and histologic parameters.

View Article and Find Full Text PDF

To define whether recanalization after occlusion can reduce the myocardial infarct size, we compared the infarct size in 25 pig hearts without collateral circulation, 35 dog hearts with collateral circulation and 11 human autopsied hearts with coronary thrombolysis at 2 to 6 hours after the onset of acute myocardial infarction. The data showed that % infarct size in the risk area increased according to the duration of occlusion. In the pig, % infarct size was 80 +/- 9% in the recanalization after 1 hour occlusion and 96 +/- 2% in the recanalization after 2 hour occlusion.

View Article and Find Full Text PDF

In an attempt to define the metabolic abnormalities of the ischemic myocardium, the changes in high energy phosphates, inorganic phosphate and intracellular pH were serially and quantitatively evaluated in ischemic porcine hearts having no collateral circulation, using arterial pressure and respiration gated in vivo 31P magnetic resonance spectroscopy. The protocol was also modified for propranolol pretreatment (0.6 mg/kg intravenously) to define its effect on the metabolism of ischemic myocardium.

View Article and Find Full Text PDF

The presence of atrial natriuretic polypeptide (ANP) was immunohistochemically demonstrated in the formalin-fixed and paraffin-embedded tissues of 25 autopsied normal human hearts using monoclonal antibody. The ANP amounts were immunohistochemically semiquantified and compared with amounts measured by radioimmunoassay (RIA). The 25 autopsied hearts were divided into 5 groups according to the interval of formalin fixation or the length of time between death and fixation.

View Article and Find Full Text PDF

To define the histopathogenesis of successful and unsuccessful recanalization following selective intracoronary thrombolysis, coronary angiography (CAG) in thrombolysis and histologic findings were compared in 13 patients who died within four days (mean 1.5 days) after the procedure. Thirteen infarct-related arteries were evaluated in respect to recanalization; presence of an intraluminal thrombus, and rupture and hemorrhage of atheromatous plaques were histologically evaluated in serial sections.

View Article and Find Full Text PDF

The postmortem histology and the results of cineangiography after selective intracoronary thrombolysis in vessels that were recanalized and in those that were not were compared in 21 patients who died within seven days (mean 2 days) of selective intracoronary thrombolysis. There was a persistent intraluminal thrombus in the infarct related coronary artery in five of six segments in which recanalisation was unsuccessful and in one of 15 segments in which recanalisation was successful. Rupture and haemorrhage of the atheromatous plaque were seen in most of the infarct related segments, both in those in which recanalisation was achieved and in those in which it was not.

View Article and Find Full Text PDF

A study of whether reperfusion accelerates cell death was performed in 35 pig hearts without collateral circulation. In 15 animals, the distal one-third of the left anterior descending coronary artery was occluded for 1 hour followed by 1-, 3-, or 7-hour reperfusion in 5 animals each. As controls, 5 hearts each were examined after 1, 2, 4 and 8 hours of occlusion of the artery without reperfusion.

View Article and Find Full Text PDF

To elucidate the expression of the atrial natriuretic polypeptide (ANP) gene in the ventricle of the human failing heart, we have measured ANP and ANP messenger RNA (ANPmRNA) levels in left ventricular aneurysm obtained at operation, biopsy specimens of left ventricles from dilated cardiomyopathy (DCM) and autopsy samples of old myocardial infarction (OMI) and DCM hearts, and compared the levels with those in the normal ventricle. The ANP level (mean +/- SE) was 17.5 +/- 6.

View Article and Find Full Text PDF

Using Northern blot analysis and radioimmunoassay, we measured atrial natriuretic polypeptide (ANP) messenger RNA and ANP levels in the ventricle in patients with old myocardial infarction and investigated the relationship between ventricular ANP synthesis and hemodynamic parameters. Levels of ANP messenger RNA and ANP were markedly increased in the left ventricular aneurysm, and a positive correlation was observed between the ANP level in the left ventricular aneurysm and pulmonary capillary wedge pressure (r = 0.85, p less than 0.

View Article and Find Full Text PDF

The distribution and progression of coronary arterial and aortic lesions were examined in 40 conventional Watanabe heritable hyperlipidemic (WHHL) rabbits. They were classified according to age into stage I (3-5 months old, 14 rabbits), stage II (6-12 months old; 12 rabbits) and stage III (14-28 months old; 14 rabbits). Fifteen normal Japanese rabbits served as controls.

View Article and Find Full Text PDF