We have conducted health examinations for 137 residents in Kosaka town, Akita prefecture, Japan since 1972, and found 10 residents with proximal tubular dysfunctions. These renal lesions identified in many residents were diagnosed as chronic cadmium poisoning induced by their mass intake of cadmium mainly via foods. Now we estimated urinary 132-microglobulin by the method of radioimmunoassay (Phadebas, β₂-micro Test, Pharmacia, Sweden). Statistically significant difference was found between the average concentration of urinary β₂-microglobulin of the Kosaka residents and that of controls in every decade from 3rd to 8th. The difference increased with age. There was a statistically significant correlation between the con-centration of urinary β-2microglobulin (ln. μg/gr. creatinine) and age (r=0.55, p<0.01, n=101). Increased excretion of urinary 132-microglobulin was associated with renal glucosuria and in-creased excretion of urinary amino-nitrogen, as well as increased urinary concentration of retinol-binding protein and lysozyme. We concluded that increased urinary excretion of β₂-microglobulin was caused from proximal tubular dysfunctions due to chronic cadmium poisoning. We believe that the average concentra-tion of urinary β₂-microglobulin of the residents in the area polluted by cadmium is a valuable index of health hazards induced by the environmental cadmium pollution.

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In order to clarify the role of renin in the hypertension of chronic renal insufficiency, 345 measurements of plasma renin activity (PRA) were made in 26 patients on maintenance hemo-dialysiso The follow up periods varied from 1 to 29 months with a mean of 14.1 months. 1. In most of the patients, PRA was increased when the body weight was reduced by restric-tion of water and sodium intake and by hemodialysisa The highest PRA value was obtained when the dry weight was achieved. 2. Twenty-six patients were divided into four groups according to the PRA at the dry weight stage. Group I (PRA values from 0 to 1.99ng/ml/h) :10 patients Group II (PRA values from 2.00 to 4.99ng/ml/h) : 7 patients Group III (PRA values from 5.00 to 90 99ng/ml/h) : 5 patients Group IV (PRA values 10.00n/ml/h and over) : 4 ioatients 3. The renin-secreting ability was considered to be low in Group I, normal in Group II and III, and enhanced in Group IV. 4. The type of hypertension was "salt and water-dependent" in Group I and II, "renin-depen-dent" in Group IV, "salt and water-dependent" or "renin-dependent" in Group III Control of hyper tension by hemodialysis was easy in Group I and II, difficult in Group III, and impossible in Group IV. 5. The primary diseases were diagnosed in 17 patients, they were chronic glomerulonephritis in 11 patients (3 in Group II, 4 in Group III, and 4 in Group IV), tuberculosis of both kidneys in 3 patients (all in Group I), and familial nephritis in 3 patients (2 in Group I and one in Group II). 6. Postmortem examination of the kidneys in 4 patients (one each in Groups II and III, and 2 in Group IV) revealed significant narrowing of the renal arterioles as compared with those in a control case. In particular, the narrowing of the interlobular arterioles with outer diameters of 50 to 200μ was remarkable in Groups II and III, and was severest in Group IV. 7. Death occurred in Groups I, II, III and N in 23, 29, 40, and 75% of the patients, respectivelya. The causes of death were hyperkalemia and shunt failure in Groups I and II, and heart failure intracerebral hemorrhage, and gastro-intestinal hemorrhage in Groups III and IV. 8. From these observations, it is concluded that the measurement of PRA is useful in choosing the treatment of the hypertension and in estimating the prognosis in patients on maintenance hemodialysis.

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The kidney specimens from 2, 079 autopsy cases excluding various glomerular diseases, were studied histopathologically. The occurrence of microthrombosis (fibrin thrombi) in glomeruli was found in 79 cases (3.8%). A, variety of glomerular changes were observed following thrombotic obliteration of the capillary lumens. However, no antecedent abnormalities were recognizable in glomeruli, which were thought to be responsible for the initiation of the thrombotic process. Statistically it was found that the incidence and severity of the thrombosis tended to become more prominent during recent years. Male patients, in particular those of aging, were more fre-quently affected than female, the ratio being 2 to 1. The thrombosis most frequently occurred in association with malignant tumors. Of these, a significantly high incidence in gastric cancer was noted (8.0%). The thrombotic lesions were also remarkable in the cases of promyelocytic leukemia and prostatic cancer. It was suggested that the recent increase in the number of glo-merular microthrombosis, which often exhibited a typical feature of disseminated intravascular coagulation, was largely the result of the improvement of therapeutic procedures, such as com-plicated surgical operations, blood transfusion, and the use of various antibitics or corticosteroid.

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It has been know that the mode of localization of antigen-antibody complexes (Complexes) in the glomerulus greately influences the form of glomerulonephritis that subsequently develops In passive serum sickness nephritis and some kind of chronic glomerulonephritis, the complexes are predominantly localized in the mesangial matrix, while in the acute serum sickness nephritis they are distributed mostely along the peripheral capillary walls e The present experiment was undertaken to elucidate factors determining the pattern of localization of complexes in the glo-menus, using different forms of soluble antigen-antibody complexes composed of different hapten-carrier conjugates, and rabbit anti-hapten antibodies with different immunochemical properties These complexes were infused into C57BL mice, and the pattern of localization of complexes was studied by light, electron and immunofluorescent microscopy. The following results were obtained : (1) Antibody affinity for the antigen has a profound effect on the pattern of localization ; complexes composed of high affin ty antibody had a tendency to be localize in the mesangial stalk region, while those composed of moderate affinity localized in pe-ripheral capillary walls other than to the mesangium. Complexes produced by extremely low affi-pity failed to le deposit ed in the glomerulia (2) Valence of the antigen and the antigen/antibody (Ag/Ab) ratio of the complexes also significantly influences the pattern of localization ; complexes composed of high valency antigen tended to be localized in the mesangial stalk region o Complexes composed of low valency antigen with a low Ag/Ab ratiowere localized in the peripheral capillary walls, while those composed of low valency antigen having high Ag/Ab ratio did not deposit in the glomeruls. It has been concluded that the molecular size of soluble complexes that is predetermined by the immunochemical properitis of either antigen or antibody significantly influences the pattern of their localization in the glomerulus.

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Juxtaglomerular granules were estimated at the individual nephron level using the Bowie-stained serial sections of the renal cortex of sodium-deprived and sodium-loaded rats. About 95% of observed nephrons possessed granules. The degree of granulation was graded in intensity of granulation from one- to four plus according to the method of Hartroft. The nephron population was examined by dividing the cortex into 5 zones of equal width from the outer to the inner portion, and the percentage of granulated or non-granulated nephrons were calculated in each zone. In control rats, the ratio of hyper-granulated nephrons to hypo-granulated nephrons was greatest in the outermost zone with a progressive decline toward the innermost zone. In sodium-deprived rats, this decline disappeared except for the innermost zone in which the ratio of granulation did not increases In sodium-loaded rats, on the other hand, the ratio of granulation significantly decreased in outer two zones but not in the other zones. The juxtaglomerular cells distended with densely packed granules are proven morphologically to constrict the afferent arteriole of the hyper-granulated nephron. Further, it would be consh dered that additional contraction of the afferent arteriole might be induced by biologically effective angiotensin II which was formed by extremely high renin activity in individual juxtaglomerular apparatus. Thus, it is evident that the glomerular blood flow is restricted at least in hyper-granulated nephrons. It may cause a shift of the renal blood flow to the other non- or hypo granulated nephrons. The specific change of the ratio of granulation depends on their sodium intake. Therefore, it may be possible that the intrarenal blood redistribution is caused mechanim cally by the swollen juxtaglomerular cells surrounding the afferent arteriole : he., the shift of the blood flow to juxtamedullary sodium-retaining nephrons under the sodium-deprived conditions, and to superficial sodium-losing nephrons under the sodium-loaded conditions.

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