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Biomedical subjects

K Hashiba

Publications and source records attributed to K Hashiba.

At least 127 records · Page 7Linked to original sources
PubMed1984

Well-controlled comparative study of the clinical effectiveness of intravenous mexiletine and procainamide on ventricular premature contraction.

In a well-controlled study the clinical efficacy of a single intravenous injection of mexiletine (3 mg/Kg) on ventricular premature contractions was compared with that of procainamide (10 mg/Kg) using continuous electrocardiographic recordings. Of the 56 subjects studied, 55 were analyzed. These consisted of 28 cases in the mexiletine group and 27 in the procainamide group. The backgrounds of both groups were considered to be equivalent. Effectiveness on VPC ("marked and moderate improvement", as judged by the subcommittee) was seen in 88% of the mexiletine group and 84.6% of the procainamide group. This difference was not significant. The duration of efficacy was almost the same in the 2 groups. Overall improvement was the same as improvement in VPC. No significant difference was observed in the incidence of side effects. Five patients in the mexiletine group and 3 in the procainamide group reported side effects. The main side effect was light-headedness in the mexiletine group and a decrease in blood pressure in the procainamide group. A decrease in blood pressure was observed in 1 case in the mexiletine group but this was restored by an intravenous infusion of noradrenaline. Mexiletine had little effect on blood pressure, while procainamide induced a drop in the systolic pressure. This difference was significant. Overall utility ("markedly and moderately useful", as judged by the subcommittee) was seen in 84.0% of the mexiletine group and 84.6% of the procainamide group. There was no significant difference between the 2 groups. From the above results, it is concluded that mexiletine (3 mg/Kg) is as efficacious as procainamide (10 mg/Kg) in the treatment of VPC but that, unlike procainamide, mexiletine has little effect on blood pressure.

Adolescent↗
PubMed1984

Effect of angiotensin III on blood pressure, renin-angiotensin-aldosterone system in normal and hypertensive subjects.

The biological actions of angiotensin III (AIII) in animals have been reported to be stimulation of aldosterone secretion and vasoconstriction. However, the biological actions of AIII in human essential hypertension (EH) have not been evaluated. Twenty ng/Kg/min of AIII was infused intravenously for 30 min into 6 normal subjects and 24 patients with EH. The systolic blood pressure was elevated significantly, from 116 +/- 5 (mean +/- SD)/68 +/- 4 to 137 +/- 9/74 +/- 5 mmHg in normal subjects and from 155 +/- 29/95 +/- 17 to 176 +/- 26/106 +/- 20 mmHg in EH patients. The elevation in systolic BP of low-renin EH patients was significantly larger than that of normal-renin EH patients. Plasma renin activity (PRA) decreased significantly from 1.64 +/- 1.07 to 1.21 +/- 1.05 ng/ml/hr in normal subjects and from 0.88 +/- 0.66 to 0.76 +/- 0.63 ng/ml/hr in EH. Plasma aldosterone concentration (PAC) increased significantly from 57 +/- 34 to 116 +/- 34 pg/ml in normal subjects and from 66 +/- 56 to 91 +/- 24 pg/ml/ in EH. There was no significant difference between the increase of PAC in low-renin EH and in normal-renin EH. Plasma cortisol concentration (PCC) did not change in these subjects. There were no significant relationships between the changes of PRA and PAC or PRA and blood pressure. These results suggest that the pressor action of AIII appeared in relation to the basal PRA in EH. In EH, PRA is suppressed by the direct action of AIII in the kidney and neither by increased PAC nor by increased blood pressure. The small changes in blood pressure caused by AII infusion suggest that a test using an AIII infusion for aldosterone stimulation would be preferable to an angiotensin II infusion.

Adolescent↗
PubMed1983

Role of renal kallikrein in control of renin release in conscious rats.

Renal kallikrein was reported to activate human inactive renin and to release active renin from rat renal cortical slices. To evaluate the role of renal kallikrein in the control of renin release in vivo, Trasylol and soybean trypsin inhibitor (SBTI) were used to determine whether they can inhibit renin release stimulated by the administration of furosemide and a 2-wk low-sodium diet. Plasma renin activity (PRA) was increased by furosemide and also by the low-sodium diet. Urinary kallikrein excretion was increased by the sodium depletions. Trasylol did not affect basal PRA; however, it inhibited PRA and urinary kallikrein excretion, when stimulated by furosemide and by a low-sodium diet. These results suggest that furosemide and low-sodium diet act on the kidney to release renin via protease production. Because SBTI affected neither PRA nor urinary kallikrein excretion stimulated by these sodium depletions, it is suggested that renal kallikrein may play an important role in the control of renin release stimulated by furosemide and by low-sodium diet.

Animals↗
PubMed1983

Neurohumoral factors in borderline hypertension.

Role of neurohumoral factors in borderline hypertension was evaluated in comparison to those in established hypertension. Although there was no significant difference in urinary noradrenaline between the 2 groups, urinary adrenaline was significantly higher in borderline hypertension than in established hypertension. During head-up tilt and Schellong's test a significant increase of diastolic blood pressure was demonstrated in borderline hypertension, whereas a significant decrease of systolic blood pressure was observed without any significant change of diastolic pressure in established hypertension. There was no significant difference in blood pressure response to cold pressor test, plasma volume, total body potassium and plasma renin activity (PRA) between the 2 groups. Blood pressure did not change after administration of captopril in normal subjects but it decreased significantly after captopril in patients with borderline hypertension even when blood pressure became normotensive during hospitalization. Blood pressure decreased significantly after captopril in patients with established hypertension. However, no significant relationship between the pretreatment PRA and the reduction of mean blood pressure was observed in both groups. It can be concluded from the present study that borderline hypertension is intermediate between normal subjects and established hypertension and that both the renin-angiotensin system and the kinin-prostaglandin system play some role in the maintenance of blood pressure in borderline hypertension.

Adolescent↗
PubMed1983

Elevation of plasma renin activity during pregnancy and rupture of a dissecting aortic aneurysm in a patient with primary aldosteronism.

This is a case report of a 37-year-old Japanese woman with primary aldosteronism who was found to have high plasma renin activity during toxemia of pregnancy and who died of a dissecting aneurysm of the aorta about 2 years later. The autopsy findings showed cystic medial necrosis in the aorta and a right adrenocortical adenoma. The dissecting aneurysm in this case is probably related to hypertension and cystic medial necrosis. A definite diagnosis of primary aldosteronism cannot be made during toxemia of pregnancy, and it is necessary to do serial determinations of plasma renin activity and plasma aldosterone concentration after delivery to confirm the diagnosis.

Adenoma↗
PubMed1982

Superior and inferior vena cava flow velocity in patients with anomalous pulmonary vein connection.

The superior and inferior vena cava flow velocities (SVC and IVC flow velocities) of 3 patients with anomalous pulmonary vein connection were recorded with the Doppler flowmeter catheter. The cases consisted of a patient with partial anomalous pulmonary vein connection to the SVC (Case 1), one with total anomalous pulmonary venous connection to the SVC (Case 2), and one with partial anomalous pulmonary vein connection to the IVC (Case 3). The SVC and IVC recordings of these patients were compared with those of 10 normal subjects, 20 patients with atrial septal defect and 150 patients with other heart diseases. The SVC and IVC flow velocities in the latter group of 180 patients showed a biphasic pattern, having systolic (S) and diastolic (D) waves, the peak S wave occurring around midsystole. In Cases 1 and 2, the SVC flow velocity showed a markedly delayed peak S wave, similar to the pattern of the pulmonary vein flow velocity; this pattern was also seen in the IVC flow velocity in Case 3. This abnormal pattern could be useful in diagnosing anomalous pulmonary vein connection.

Adolescent↗
PubMed1982

[General pharmacology of T-1982, a new cephamycin antibiotic].

General pharmacological studies on T-1982 produced the following results. On central nervous system, subcutaneous injection of T-1982 at dose of 2,000 mg/kg hastened the onset of pentetrazole-induced tonic extensor in mice. T-1982 had no effect on spontaneous motor activity, pentobarbital hypnosis, body temperature or EEG in mice or rabbits, and also did not show motor incoordinate, anticonvulsive or analgesic activity in mice at intravenous doses of 250--1,000 mg/kg or subcutaneous doses of 500--2,000 mg/kg. On motor and sensory nervous systems, no effect of T-1982 was noted on spinal reflex, neuromuscular junction, conduction anesthesia or surface anesthesia in rats or rabbits. On respiratory, cardiovascular and autonomic nervous systems, T-1982 caused transient increase of respiratory rate, slight hypotension and transient increase of femoral blood flow in dogs at intravenous doses of 250--1,000 mg/kg. However, it caused a slight hypertensive tendency in rabbits. Heart rate and ECG in dogs or rabbits, blood pressure response to epinephrine, isoproterenol, acetylcholine or histamine in dogs, nictitating membrane in cats and pupil size in mice were not affected after intravenous injection of T-1982. No effect was found on isolated guinea pig atrium or rabbit descending aorta following T-1982 application. On renal function in rats, T-1982 caused an increase of PSP excretion but had no effect on urine volume or electrolytes excretion at intravenous doses of 250--1,000 mg/kg. T-1982 prolonged bleeding time in mice at intravenous doses of 500--1,000 mg/kg, but did not show hemolytic property and inhibitory activity on blood coagulation or platelet aggregation in vitro experiments. Spontaneous movement and tone of isolated stomach, ileum, colon, uterus, vas deferens or trachea and acetylcholine-, histamine-, nicotine- or barium chloride-induced contraction of ileum were not affected following T-1982 application. Intestinal propulsion of barium meal in mice, gastric secretion and carrageenin-induced edema in rats were not affected after intravenous injection of T-1982. T-1982 increased bile secretion in rats dose-dependently at intravenous doses of 31.3--125 mg/kg. The local irritative activity of T-1982 in rats was slightly milder than cefoxitin and moderately milder than cefmetazole after intradermal injection. In conclusion, these results suggest that T-1982 would not cause any adverse effects at its estimated clinical doses of 10--20 mg/kg (500--1,000 mg/man).

Animals↗
PubMed1981

Correction of hypertension by partial nephrectomy in segmental renal artery stenosis and electron microscopic studies of renin.

An 18-year-old man had hypertension with hyperreninemia and marked difference in plasma renin activity between both renal veins after tilting. Selective renal arteriography revealed a stenotic lesion in a segmental artery to the upper pole of the left kidney with poststenotic dilatation. The upper pole of the kidney with abnormal arterial segment was resected and the blood pressure returned to normal. Electron microscopically, a large number of mature juxtaglomerular cell granules were associated with many protogranules in the epitheloid cell. These findings suggest that his hypertension was due to overproduction of renin from the upper pole.

Adolescent↗