Search PubMed⌕ Search

Biomedical subjects

K Ogino

Publications and source records attributed to K Ogino.

At least 181 records · Page 10Linked to original sources
PubMed1987

On the ionic mechanism of cyproheptadine-induced bradycardia in a rabbit sinoatrial node preparation.

The effects of cyproheptadine (0.1-10 microM) on the membrane potentials and currents of rabbit sinoatrial node were examined with the double-microelectrode voltage clamp technique. Cyproheptadine reduced the heart rate, maximum rate of depolarization and action potential amplitude. It also decreased the slope of phase 4 depolarization. On the current systems, cyproheptadine decreased the slow inward current (Isi), the time-dependent potassium outward current (Ik) and the hyperpolarization-activated current (Ih). The reduction of Isi was the major effect. Furthermore, Isi was progressively decreased by repetitive membrane depolarization during administration of cyproheptadine, an effect suggestive of frequency-dependent block of Isi. These electrophysiological observations indicate that cyproheptadine has a calcium antagonistic property, and additionally, decreases Ik and Ih in rabbit sinoatrial node.

Action Potentials↗
PubMed1987

Inhibition of Ca2+ inward current in rabbit sinoatrial node by bunazosin, an alpha-adrenoceptor antagonist.

The electrophysiological effects of bunazosin, a novel alpha-adrenoceptor antagonist, were examined on isolated spontaneously beating sinoatrial node preparations of the rabbit by means of a double-microelectrode voltage clamp method. Bunazosin (above 10 microM) reduced the beating frequency, and the maximum rate of rise and the amplitude of action potentials. The slope of the diastolic depolarization (phase 4) was also decreased by the drug whereas the action potential duration at 50% repolarization was prolonged. Bunazosin decreased the slow inward current (Isi) and the time-dependent potassium outward current (IK). However, the major effect was the reduction of Isi. The results indicate that bunazosin, an alpha-adrenoceptor antagonist, depresses the action potential and automaticity of the sinoatrial node by inhibition of Ca channels.

Action Potentials↗
PubMed1987

Alteration of chloral hydrate metabolism in rats with carbon tetrachloride-induced liver damage.

The metabolism of chloral hydrate (CH) was investigated in the isolated perfused rat liver system. The experiments were performed on rats that were administered carbon tetrachloride (CCl4) subcutaneously for 15 weeks to induce chronic liver damage and on untreated rats. Clearance of CH from the perfusion system was lower in damaged liver than in control liver. In both groups, 50-70% of the added CH was excreted into perfusate as trichloroethanol (TCE) and trichloroacetic acid (TCA) within 120 min. The TCE/TCA ratio was 1:1.3 in the control group compared to 2:1 in the damaged liver group. The findings suggest that CH metabolism in the liver is affected by chronic damage.

Animals↗
PubMed1987

A case of four coronary artery fistulae originating from three vessels associated with aneurysm.

A case of an aneurysm associated with four coronary artery fistulae originating from three vessels is reported. The patient, a 52-year-old woman, had chest heaviness and palpitations. Coronary arteriography revealed the four fistulae originating from three coronary vessels with an aneurysm draining into the left ventricle and the main pulmonary artery. The patient's symptoms were relieved after fistulectomy and the aneurysmectomy, suggesting that a coronary steal phenomenon through the fistulae was the cause of her symptoms. This case is of interest because of its rarity, since this is the first case report of an aneurysm associated with four coronary artery fistulae from three vessels.

Arterio-Arterial Fistula↗
PubMed1987

Cardiac involvement in a patient with limb-girdle muscular dystrophy.

A case of limb-girdle muscular dystrophy with cardiomegaly, electrocardiographic abnormalities, and paroxysmal ventricular tachycardia was described. Some of the interesting electrocardiographic features were discussed, and the importance of serial electrocardiograms for the detection of cardiac involvement is emphasized, since acute disturbances in cardiac rhythm may indicate that the patient is in immediate danger of sudden death.

Cardiomegaly↗
PubMed1987

Electrophysiological study of cibenzoline in voltage-clamped rabbit sinoatrial node preparations.

Effects of cibenzoline (0.1-30 microM) on membrane potentials and currents were investigated in rabbit sinoatrial node cells using conventional microelectrode and double microelectrode voltage clamp methods. Cibenzoline reduced the heart rate, the maximum rate of rise and the action potential amplitude in a dose-dependent manner. At the same time, the action potential duration at half-amplitude was prolonged, and the slope of phase 4 depolarization was decelerated. The voltage clamp experiment revealed that cibenzoline (7-30 microM) depressed the slow inward current, the time-dependent potassium outward current and the hyperpolarization activated current. Neither the kinetic variable of the time-dependent potassium outward current nor the decay time of the outward current tail was altered by the drug perfusion. The results suggest that cibenzoline exerts a depressant effect on the electrical activity of sinoatrial node cells and that the depression of the currents induced by cibenzoline is due to a reduction in conductances of the current systems.

Action Potentials↗
PubMed1987

[Quality of life after resection of the stomach].

The quality of life after operation was analyzed using a questionnaire from 283 patients who received gastrectomy between 1972 and 1983 at Kobe University Hospital. Kruskal-Wallis analysis and Dunn's multiple comparison analysis were used to analyze multiple factors consisting of background, therapeutic and prognostic factors when the level of social activity is considered as the final evaluation. Categorical principle component analysis was used to examine the relationship among each factor and to verify the former results. The background factors played an important role for the outcome (i.e., longer survivors and/or patients with beign disease had better outcomes and patients over 60 years and/or with body weight less than 50kg had worse outcomes). In the analysis of therapeutic factors, it was suspected that suitable resection under suitable curability and/or suitable reconstruction method in the total resection of the stomach contributed to a better outcome. Also, therapeutic control of diarrhea after gastrectomy was suspected as being important among the many prognostic factors.

Adult↗