The filtration fractions of the plasma flows, supplying partly the superficial cortex and partly the deep cortex were calculated by measuring the plasma concentrations of protein and inulin in blood collected simultaneously from an artery, from the subcapsular vein and from the deep vein of the cat kidney. Relationship between the filtration fraction of the superficial cortex (FF_S) or of the deep cortex (FF_D) and sodium reabsorptive rate was studied during several maneuvers. The change of corrected intrarenal hematocrit (Ht) was calculated simultaneously. (1) FF_D and sodium reabsorptive rate were both significantly lower in cats fed a high-salt diet than in cats fed a low-salt diet. FF_S were equal in both groups. (2) The decrease in FF_S and in FF_D (especially in FF_D) were observed by acute rapid Ringer loading and the subsequent decrease in sodium reabsorptive rate was occured. (3) Decreased arterial blood pressure by partial abdominal aortic constriction during mild Ringer loading resulted in decrease of FF_S and of FF_D(especially of FF_D), but sodium reabsorptive rate was not decreased. (4) Hematocrit (Ht) of subcapsular venous blood (Ht_S) was higher than that of arterial blood (Ht_A) and Ht of deep venous blood (Ht_D) was lower than HtA. These relations were remained stable with Ringer loading. (5) Intrarenal Ht was not changed significantly both by partial abdominal aortic constriction and by renal vein constriction. There was no relationship between the change of intrarenal Ht and the autoregulation of renal circulation. These observations suggest that the change of intrarenal filtration fraction (predominantly decrease of FF_D) has an important role on sodium reabsorption but the change of intrarenal filtration fraction has no effect on sodium reabsorption under abdominal aortic constriction. The change of intrarenal hematocrit is not a factor to regulate sodium reabsorption.

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Acute thoracic inferior vena caval constriction (TIVC) abolishes or markedly blunts the natriuretic response to an intravenous infusion of saline. However, acute TIVC produces marked systemic and renal hemodynamic changes which in themselves have been shown to affect sodium excretion. To evaluate the antinatriuretic effect of the systemic hemodynamic changes during TIVC, studies were performed in anesthetized, vasopressin and mineralocorticoid received dogs. After acute volume expansion by isotonic saline, the effects of acute TIVC on sodium excretion rate (Na ex %) were observed. Following the release of TIVC, acute aortic constriction (AOC) and acute abdominal inferior vena caval constrictiction (AIVC) were simultaneously performed so that to reproduce the aortic pressure and the inferior vena caval pressure during TIVC. Na ex % decreased from 14.2% to 7.1% during TIVC, and from 14.7% to 9.3 % duringAOC+AIVC. The decrements in Na ex % during TIVC were significantly greater than those during AOC+AVC, whereas the decrements in GFR and in RPF were not significantly different in both maneuvers. The decrease in Na ex % was also observed during AIVC alone, but the decrements in Na ex % during AIVC were smaller than those during TIVC or during AOC+AIVC. It is concluded that the antinatriuretic effect of acute TIVC is mainly due to renal hemodynamic changes, but partially due to unknown factor which may be activated by systemic hemodynamic changes.

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We have mesured individual amino acid content plasma of the patients and the dialysate by means of an auto amino analyzer. By a Kolff type dialyzer 500 mg/hr. Kiil type dialyzer 600800 mg/hr. of total amino acid is lost to dialysate, whereas 1000 mg/hr. is filtered by a HFAK type dialyzer. A significant amount of amino acid is dialyzed across the cuprophan and HFAK membrance. All the patients exhibited an amino acid imbalance in which there was a significantly lower percentage of essential amino acid in the total amino acid (E/T). A correlation was observed between the creatinine and E/T ratio (Y=-1.268×+56.47). It is conculuded that both inadequate dietary intake and degree of uremia contribute to the amino acid imbalance. Threrefore, either protein of the high biological value or essential amino acid supply should be taken into consideration for the patients undergoing chronic dialysis.

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One of the major obstacles impeding the further expansion of chronic hemodialysis in Japan is that hemodialysis equipments are too big and also hard to handle . So we think that smaller and more easily handled equipments are needed. It is necessary to make dialysate volume lower in making a smaller equipment. A dialysate regenerating system is indispensable to make such equipments. So we have studied on a dialysate regenerating system using several adsorbents. We have carried on the research of adsorbents such as activatedd charcoal, aluminum oxide, magnesium oxide, kaolin, bone charcoal and ion exchanges. Above these 6 adsobents were examined with ultrafiltrates through SCUM, obtained from uremic patients. Aluminum oxide and magnesium oxide adsorbed inorganic phosphate efficiently and we though that activated charcoal was an excellent adsorbent. However no adsorbents adsorbed urea efficiently. As one step towards DIFAK, we have tried to make a machine incorporated with 301 of dialysate, activated charcoall and aluminum oxide. 301 of dialysate is almost the same volume as human body fluid. Theoretically, when the resistance of the membrance is neglected, the serum urea concentrations of the patients become half after dialysis using 301 of dialysate. Creatinine and uric acid might be removed efficiently by using activated charcoal. Inorganic phosphate might be removed by using aluminum oxide. The removal rates of substances in uremic patients were measured in conventional hemodialysis andd hemodialysis using 301 of dialysate. The removal rates of substances which are larger than 300 in moecular weight in 30l-dialysate-dialysis are the same as those of conventional hemodialysis. But the removal rates of the substances smaller than 300 in molecular weight in 301 dialysate dialysis are worse than conventional hemodialysis. But small molecular subtances such as creatinine and uric acid, couldd be removed efficiently by activated charcoal. So we believed that our new equipment -DIFAK- incorporated with 301 of dialysate, activatedd charcol and aluminum oxide is beneficial to making a small equipment.

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In order to lessen the amount of electric power needed to operate the dialysate supply system, to make free from the plumbing and to make the equipment more compact and easier to handle, we have developed a new portable machine with 30 h dialysate and adsorbents. We call this machine Dialysate Free Artificial Fidney-DIFAK- The volume of dialysate is only 30 L, and this 30 L of dialysate is filtrated through activated charcoal and aluminium oxide, and recirculated during hemodialysis. The volume of dialysate has been set at 30 L in due consideration of safety, as a result of careful testings and calculations. The activated charcoal and aluminium oxide are used as adsorbents. The activated charcoal is specially purified and adsorbs creatinine, uric acid, phenols, guanidine bases and organic acids. Aluminium oxide is granular and insoluble and adsorbs inorganic phosphorus. Therefore we have made home dialysis and bed-sidedialysis in the hospital easier with this machine. We have carried out 266 dialyses on 6 patients with this machine for two years. One dialysed patient has been on home dialysis for 10 months. No patients have ever had any side effects because of mechanical failure in any point of the procedure. When the hemodialysis treatments are carried out through this machine in combination with Hollow Fiber Kidney, the removal rate of waste metabolites is superior to the conventional hemodialysis and this equipment becomes smaller. It can be concluded that with the completion of this machine it is not necessary to prepare a special room in the hospital for dialysis, or to construct a new room for home dialysis. Therefore this machine -DIFAK- is highly recommended for your consideration in that it represents a positive step towards an efficient and cheeper method for the hemodialysis in the home as well as in the hospital.

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The ultrasupernatant of kidney homogenate treated with pronase has a strong antigenic activity of tubular epithelial cells but a faint activity of GBM. Insoluble human tubular epithelial antigen (Tub-Ag) was prepared from autopsied normal kidneys, using the method of Edgington et al., and solubilized with pronase-treatment, followed by ultracentrifuge. Albino rabbits were immunized with the soluble tubular epithelial antigen(Pr-Tub-Ag). The γ-globulin fraction of the antiserum was conjugated with fluorescenn iso-thiocyanate (FITC). This reagent stainened specifically the luminal layer of proximal tubules of normal human kidney section. Biopsy specimens were obtained from the kidneys of 34 patients (7 cases with membranous glomerulonephritis (mb-GN), 4 with lipoid nephrosis, 7 with proliferative glomerulonephritis, 10 with collagen disease and 6 with other miscellaneous diseases) and their cryostat sections were stained with each of FITC-labeled antisera to human immuno- and BIC-globulins, albumin and fibrinogen as well as withFITC-labeled antiserum to human Pr-Tub-Ag. When the FITC-labeled antiserum to Pr-Tub-Ag was used, specific fluorescence was found in the proximal tubular epithelium in all cases tested. In addition, in 3 out of 7 cases with mb-GN, uniform granular fluorescence was observed along the glomerular capillary walls in a fashion similar to that of IgG deposition. In the other 4 cases with mb-GN and 2 with lupus nephritis, in which the GBM were stained in uniform bead-like pattern with anti-IgG, no fluorescent staining with anti-Tub-Ag was observed in the glomeruli. It could be said from these results that autologous tubular epithelial antigen was demonstrated as one of the causative antigens in human mb-GN.

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