The intracellular potential of renal tubule of rats was measured with the microelectrode and effect of desoxycorticosteroneglucoside (D. C. G) upon the intracellular potential was examind in relation to the transport of Na and K through tubular cells. The outline of the experimental results is as follows: 1) The intracellular potential of proximal tubule was-65±11 mV at the interstitial side, while thatof the distal tubule was-63±12 mV. The transtubular potential was-19±4 mV in the proximal tubule, while-23±8 mV in the distal tubule. 2) After administration of D. C. G, these potentials all tended to increase, and secretion of K through tubular cells seemed to be accelerated at the same time. 3) Adopting the K potential hypothesis of Giebisch on the tubular potential, it was inferred that activating the M^a-K exchange pump of the tubular cell membrane, D. C. G may increase K concentration in the tubule cells, and increase the Na reabsorption through the tubule. The increase of intracellular potassium concentration may promote the secretion of K into the urine.

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I Relationship with diuresis and the change in ATPase activity. 1) Significant changes in ATPase activity is not observed not only in the cortical Homogenate (H) but Mitochondria (Mt), Michrosome (Mc), and Supernatant fraction (S) under the mannitol diuresis. In contrast to this, it is apparently found that, in the medulla, ATPase activity in Mt fraction elevates and that in Mc fraction slightly increases. 2) No specific change is seen under the diuresis with Ringer's solution and Igrosin, which is considered to be the same alteration under the osmotic diuresis by mannitol. In other words, no distinctive change is seen both in the cortical H, Mt and Mc fractions, and the activity in the medulla is changed to the same degree with mannitol diuresis, 3) Under the diuresis of the administration of chlorothiezide alone, urine volume, of inary sodium and potassium excretion increases, and the ATPase activity in the cortical Mc fraction is characteristically elevated. Therefore, a marked correlation is considered to occure between the change in ATPase activity in the cortical Mc fraction and water and solute diuresis. This mechanism may not be clearly elucidated but it is possible that the ATPase activity, which is mainly localized in the cell and vacuoles membranes, has a large role to play, and that it has a close relationship with electrolyte transport across the cell membranes of the renal tubules. II Correlation of the change in Succinoxidase activity with diuresis, 1) Under the diuresis with Ringer's solution and chlorothiazide, as in the osmatic diuresis by mannitol, the Succinoxidase (S-Oase) activities of the Mt at the cortex and medulla are remardably increased. 2) A tendency is observed that S-Oase activity at the Mt fraction under the administration of Igrosin is found to be lower than that in the above. This may be due to the inhibitation of S-H radical in Mt by organic silver.

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It has been previously reported by S. Shibata that the chemical analysis of ultrasupernatant of the kidney emulsion of animals (rabbit, rat and dog) treated with trypsin represents an excellent approach towards the elucidation of the chemical state of the glomerular basement membrane. In 165 autopsy cases, subsequently, chemical analysis of the ultrasupernatant of trypsic digestion of human kidney and histological observation on the kidney were performed. In 32 histologically normal kidneys, the mean value of nitrogen (N), hexosamine (Hex.) and phosphorous (P) were 11.3%, 1.99%, and 0.34% respectively. The N level was nearly constant regardless of the age and diseases. Increased Hex. and P levels were invariably found in cases with thickening of the glomerular basement membrane and increased mesangium. Almost all of these cases belonged to either diseases of the liver, or renal and collagen diseases. In cases of uremia (contracted kidney), however, an increase of Hex. and decrease of P (the mean value in uremic 11 cases were N; 11.0%, Hex. ; 2.41%, P ; 0.28%) were found. In nepnrosis, diabetic nephropathy, nephrosclerosis and lupus-nephritis chemical data showed higher Hex. and P, while the weight of the kidney was kept within normal limits. In the diseases of the liver (24 cases) the mean values of N, Hex. and P were 10. 4%, 2.71% and 0.45% respectively and thickening of the basement membrane and increased mesangium were remarkable. These histological features resembled those of glomerulonephritis. It might be concluded that there is a close correlation between chemical data and histological findings of the basement membrane and mesangium. Clinically proteinuria is rarely found in liver diseases. It seems, therefore, that there is a distinct difference in the chemical component of basement membrane between the liver and kidney diseases. In order to solve this problem analysis of hexosam ine in ultrasupernatant of the kidney treated with trypsin are performed after development on a paper chromatogram. A dominance of glucosanime over galactosamine was found in the basement membrane in chronic nephritis, corresponding to our findings in experimental nephritis. Galactosamine, on the other hand, was dominant in glomerular basement membrane in cirrhosis of the liver. These results might give a clue to the understanding of the role of polysaccharide in the development of the renal lesion in cirrhosis of the liver.

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The nephrotic syndrome is characterised by edema, proteinuria, hypoproteinemia and hyperlipemia. It is supposed that the symptom may depend on various metabolic abnormalities based on hypoproteinemia. The present paper reported a study on albumin metabolism using I¹³¹-labeled human serum ablumin in 12 cases of nephrotic patients and 1 case without renal lesion. The patients were classified into 4 groups. In group A, the patienrs were all in marked nephrotic state and not under the treatment of glucocorticoids. In group B, the patients recieved a large amount of glucocorticoids. In group C, the patients were improved from severe nephrotic state by glucocorticoid therapy and discontinued the therapy at the time of measurement of albumin metabolism. In group D, the patients were obtained The complete remission and discontinued the therapy. The conclusions obtained from this study as follows.: 1. Marked decreased half-life of albumin degradation, marked increased turnover rate and decreased total exchangeable albumin were noted in the patients belonging to group A. Albumin catabolism in the body (grm/day) were observed within normal limits and albumin turnover rate in the urinary logs increased in group A, In 1 patient of group B showing a poor response to glucocorticoid therapy, the albumin metabolism was the same in group A. In another patient with a good response to the therapy, however, the albumin metabolism was similar to that of group C. In group C, abnormalities of albumin metabolism were less than that of group A, and albumin metabolism in group D were observed within normal limits, 2. It might be concluded that hypoalbuminemia in the nephrotic syndrome primarily was resulted from urinary albumin loss and that the increased albumin turnover rate in the body accelerated nephrotic hypoalbuminemia after accomplishment of decrease of total exchangeable albumin. 3. Increased albumin synthesis was seen in the nephrotic syndrome. A reverse correlation was found between the rate of increased albumin synthesis and decreased plasma albumin concentration, the lesser plasma albumin concentration, the more albumin synthesis increased. When glucocorticods were treated with large dosage, however, the rate of albumin synthesis increased itself regaraless of plasma albumin concentration in the nephrotic syndrome. 4. The effects of glucocorticods on nephrotic patients were considered that improved permiability of glomerular capillary basement membrane might result the decrease of proteinuria and that increased protein catabolism by glucocorticoids might be compensated increased albumin synthesis.

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As one of studies to clarify patho-physiology in nephrosis, the metabolism of phosphate compounds in the liver and kidney of nephrotic rats produced by Aminonucleoside (AN) administration was studies. The results were as follows : 1) In the liver of nephrotic rats, the acid-labile phosphate (high energy phosphate) concentration did not change, but its specific radioactivity significantly increased, and total acid-soluble phosphate concentration and its specific activity slightly increased. Inorganic phosphate slightly increased in the liver of nephrotic rats, but rate of P32 incorporation into inorganic phosphate did not change. It is concluded that energy metabolism raises in the liver of nephrotic rats.2) In the liver of nephrotic rats, the concentration of ribonucleic acid-phosphate (RNA-P) and deox-yribonucleic acid-phosphate (DNA-P) and specific radioactivitis into RNA-P & DNA-P markedly increased. It is assumed that nucleic acids synthesis increases in the liver of nephrotic rats. Such high nucleic acids metabolism should be regarded as a form of response to the increase in the protein synthesis in the liver of nephrotic rats.3) It was found that the number of cells showing mitotic figure or double nuclei increased in the liver of nephrotic rats. The histological findings may agree with the increasing synthesis of DNA in the liver of nephrotic rats.4) In the kidney of nephrotic rats, the inorganic phosphate content in the acid-soluble fraction incre-ased, but other phosphate compounds decreased. The rate of P³² incorporation into acid-labile phosphate slightly decreased. It is supposed that energy metabolism slightly decreases in the kidney of nephrotic rats. The content of RNA-P and DNA-P in the kidney also decreased, but those specific radioactivities did not change in normal and nephrotic rats. It is concluded that nucleic acid-phosphate concentration in the kidney of nephrotic rats appearently decreases because of tissue edema, but the true concentration remains to be unchanged in the kidney tissue.

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Since Oshima gave a report of the hypertension on the 16 th Annual Congress on Japanese Circulam tion, a role of renin-angiotensin system in the hypertension has been studied. The comparative studies on renal function, water and electrolyte metabolism of normal dogs, goldblatt's dogs, hypophysectomised dogs, hypophysectomisednephrectomised dogs, normotensive and hypertensive patients during the infusion with synthetic angiotensin II, Renin, Noradrenaline and also the influence on aldosterome secretion were performed. Angiotensin II decreased GFR and RPF of both normal and hypertensive subjects, the reduction in RPF being more predominant than that of GFR. Angiotensin II decreased urine volume, sodum excretion and the urinary sodium: potassium ratio in the normotensive, but the increase in urine volume and sodium excretion in the hypertensive was observed. Noradrenaline showed no definit result. Angiotensin II stimulated the aldosterome secretion in normal and goldblatt's dogs, hypophysecto-mised and hypophysectomisednephrectomised dogs. In human being, angiotensin II increased the excretion of aldosterone while noradrenaline did not increase. As previously, it appears to be thinkable that synthetic angiotensin II decreases GFR and RPF by means of marked constriction of the renal arterioles and simultaneously stimulates the aldosterone secretion through the direct action on the zona glomerulosa of adrenal glands. It is convinced that in the normotensive the stimulating aldosterone results in the decrease in urine sodium excretion, but the paradox phenomen in the hypertensive is unclar. Therefore the more precise mechanism of the effectt of angiotensin II, influencing electrolyte metabolism, on the renal function should be studied.

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