The present study was undertaken to evaluate the relationship between renin secretion from the denervated kidney and intrarenal distribution of blood flow during reductions in renal perfusion pressure by partial constriction of the aorta with and without ureteral occlusion in the anesthetized dog. In addition, renin contents in different zones of the kidney were measured. A reduction in renal arterial pressure from normal pressure (125-135 mmHg) to 77 mmHg resulted in significant increase in renin secretion and redistribution of cortical blood flow. A further reduction of renal arterial pressure to 51 mmHg produced a marked increase in renin secretion rate (RSR) without further changers in the intrarenal distribution pattern of blood flow. The pressure reductions during ureteral occlusion increased RSR without any change in the distribution pattern of blood flow, and a decrease in the amounts of extractable renin was found in the outer cortex of the experimental kidney. These findings suggest that renin release occurs mainly in the outer cortex, and this process may be stimulated when the mechanism of autoregulation fails as the perfusion pressure approaches to the lower range autoregulation in the outer cortex.

View full abstract

To define the etiologic factors of Japanese cerebrovascular diseases, a pathological research was conducted on autopsy cases of stroke in Akita Prefecture. In most cases of cerebral hemorrhages, especially in the middle age group (30-59 of age), arteriosclerotic deviations in basal cerebral arteries of the circle of Willis and intracerebral small arteries are not found. The authors conclude that cerebral hemorrhage may occur without relationship to disturbances of lipid metabolism, biochemically, and to atherosclerosis, pathologically. Concerning cerebral infarction, especially in the old generation (over 60 years of age), severe arteriosclerotic deviations were recognized both in basal cerebral and intracerebral arteries. These changes were highly influenced by the grade and duration of hypertension, and rarely influenced by hyper-cholesterolemia. According to the above-mentioned facts, the results obtained from our epidemiological survey were confirmed by the pathological studies.

View full abstract

The quantitative detection of cerebral arteriosclerosis by means of the pressure-velocity hysteresis technique composed of the cerebral blood velocity pattern (blood velocity pattern in the internal carotid artery measured by the ultra-sonic Doppler technique) and the cerebral pressure pulse pattern (common carotid arteriogram measured by non-invasive sphygmography) was investigated in 17 normal young males, normal middle-aged males and patients with cerebral vascular disorders. The ratio of blood pressure/blood velocity in the maximum blood velocity was used as a measure of resistance of the blood flow. The resistance of the cerebral blood flow was significantly increased in the patients with cerebral vascular disorders compared to that in the normal young males. The resistance of cerebral blood flow in the middle-aged males was prone to be intermediate between the former two. The results suggest that the pressure-velocity hysteresis technique is useful for the quantitative detection of cerebral vascular resistance as well as cerebral arteriosclerosis. Several factors related to the technique were discussed.

View full abstract

The conduction system of seven cases died of the so-called "Pokkuri disease", was histopathologically studied with serial sectioning method. Fibrosis with a significant reduction of conduction fibers was observed in the sinoatrial node and unction between the node and atrial muscle fibers in 6 cases. Abnormal course and branching of the sinus node artery was seen in 6 cases of which 3 had no penetration o fits main branch into the node. Some pathological lesions exsisted in the atrioventricular conduction system in 4 cases: 2 had fibrotic lesion in the distal bundle of His and proximal left and right bundle branches which were sandwiched between the abnormal conal muscle and the summit of ventricular septum. Remaining 2 had lipomatous partial interruption in the mid- and distal bundle of His. Simultaneous involvement of sinoatrial node and the atrioventricular conduction system was observed in 4 cases. One of such cases showed abnormal ECG consisted of a left axis deviation and right bundle branch block. As a conclusion, pathological lesions in the conduction system are revealed in more than half of cases of "Pokkuri disease". The pathgenesis seems to be related to minor anomalies such as abnormal sinus node artery, abnormal conal muscle situation.

View full abstract

Immunofluorescent studies were performed on 217 percutaneous renal biopsies on patients with various renal diseases, which were examined in detail to assess the amount, character, and distribution of fibrin deposits in the glomeruli. The fibrin deposits were classified into six different forms on immunohistologic grounds. These were adhesive, adhesive and occlusive, membranous, mesangial, crescent forming, and sclerotic types. The sclerotic type was further subdivided into 2 groups: periglomerular fibrosing, and sclerosis with occlusion types. In many instances, immunofluorescence may reveal a pattern which is commonly associated with a characteristic abnormality on light microscopy. Fibrin deposits were commonly correlated with the presence of glomerular immunoglobulin and βIc/βIa-globulin. These findings interpreted as the immune reaction within glomeruli leads to an initiation of the coagulation process. The pathogenesis of each type of fibrin deposits and the sequences of glomerular hyalinization are briefly discussed.

View full abstract

Time-course changes in blood pressure, urinary norepinephrine and dopamine excretion after administration in a single dose of fusaric acid calcium salt were examined in 8 elderly hypertensive patients. Eight elderly hypertensive patients served as controls receiving placebo administration in a single dose. The dose of fusaric acid calcium salt ranged from 5.1 mg/Kg to 6.0 mg/Kg. The results obtained are as follows: 1) Both systolic and diastolic blood pressure showd a significant reduction in fusaric acid calcium salt group, the lowest value of systolic blood pressure being observed from 4 to 8 hrs. and that of diastolic blood pressure being observed from 4 to 6 hrs. after administration of this agent, respectively. Systolic blood pressure returned more slowly to the level before fusaric acid calcium salt administration than diastolic blood pressure did. In placebo group, however, no significant reduction of both systolic and diastolic blood pressures was noted. 2) In fusaric acid calcium salt group, norepinephrine excretion in the urine did not show a diurnal change. In placebo group, however, a tendency of diurnal change was noted. These results would suggest that noepinephrine synthesis might be inhibited temporalily by fusaric acid calcium salt. 3) In fusaric acid calcium salt group, dopamine excretion in the urine did hardly show a diurnal change. In placebo group, however, a fairly evident diurnal change was observed. The interpretation of these results seems to be difficult in the present state of knowledge of the action of fusaric acid calcium salt in humans.

View full abstract

It has been known for along time that weak stimulation of the afferent somatic nerve causes depressor responses, but as the stimulation is intestified, pressor responses appear. There are papers by Johason as well as by Sato on these phenomena, in recent years. It has been revealed in the experimental studies on anesthetized dogs made in author s laboratory that afferent somatic nerve stimulation of the forelimbs gives predominantly pressor responses, and of the hindlimbs predominantly depressor responses. In this study, afferent stimulation of the somatic nerves were applied on anesthetized depressor responses, namely, observing the blood pressure, heart rate and cardiac output, terms of the effects of artificial pacing, section of the vagus nerve, atropine treatment, propranolol treatment and treatment with ganglion blocking agent. Analyzing the mechanism of blood pressure responses from the aspect of hemodynamics, the author came to the conclusion that the blood pressure responses are, in most part, attributable to dilation and contraction of the resistant blood vessels.

View full abstract