Summary
In micropuncture experiments on rat kidneys early distal sodium concentration, approximating that of the macula densa site, together with glomerular filtration rate and renal excretory function were determined before and after renal ischemia or hemorrhagic hypotension. In the ischemia experiments micro-puncture samples were obtained using the same early distal puncture site of distal convolutions before and after ischemia.
Early distal [Na+] was found to be increased after ischemia or hypotension, in some experiments approaching plasma [Na+]. The degree of increased [Na+] was inversely related to GFR. In order to eliminate the influence of reduced tubular flow rate which occurs after renal ischemia, single loops of Henle were perfused at a constant rate and the increase in early distal [Na+] was found to be in the same range of magnitude. U/P inulin was decreased after renal ischemia. U Na·V and urine volume were increased in most experiments.
The results indicate that the ability of the ascending limb of Henle's loop to establish a [Na+] gradient across the tubular wall is reduced after renal ischemia or hemorrhagic hypotension. According to the hypothesis that GFR is regulated by [Na+] at the macula densa cells, it is suggested that persistent renal vasoconstriction and fall in GFR following renal damage is caused by the elevated [Na+] of the tubular fluid in the macula densa segment. It is concluded that reduction of RBF and GFR after renal damage is the response to decreased tubular Na+ reabsorption, and that the renin angiotensin system participates in this reaction at the level of the juxtaglomerular apparatus. The reaction is considered as a Na+-conserving mechanism.
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Literatur
Biber, Th. U. L., M. Mylle, and C. W. Gottschalk: Micropuncture study of kidney function in rats with experimental tubular necrosis. Excerpta Med. Found., Congr. Ser. 78, 21 (1964).
Bohle, A.: Kritischer Beitrag zur Morphologie einer endokrinen Nierenfunktion und deren Bedeutung für den Hochdruck. Arch. Kreisl.-Forsch. 20, 193 (1954).
Borkowski, A. J., S. S. Howards, and J. H. Laragh: Angiotensin and electrolyte excretion in renovascular hypertension. Amer. J. Physiol. 208, 1087 (1965).
Brun, C., and O. Munck: Pathophysiology of the kidney in shock and in acute renal failure. Progr. Surg. (Basel) 4, 1 (1964).
Bucher, O., u. E. Reale: Zur elektronenmikroskopischen Untersuchung der juxtaglomerulären Spezialeinrichtungen der Niere. II. Über die Macula densa des Mittelstückes. Z. mikr.-anat. Forsch. 67, 514 (1961).
— Zur elektronenmikroskopischen Untersuchung der juxtaglomerulären Spezialeinrichtungen der Niere. III. Die epitheloiden Zellen der Arteriola afferens. Z. Zellforsch. 56, 344 (1962).
Cortney, M. A., W. Nagel, and K. Thurau: A micropuncture study of the relationship between flow-rate through the loop of Henle and sodium concentration in the early distal tubule. Pflügers Arch. ges. Physiol. 287, 286 (1966).
Deetjen, P., u. K. Kramer: Die Abhängigkeit des O2-Verbrauchs der Niere von der Na-Rückresorption. Pflügers Arch. ges. Physiol. 273, 636 (1961).
Flanigan, W. J., and D. E. Oken: Renal micropuncture study of the development of anuria in the rat with mercury-induced acute renal failure. J. clin. Invest. 44, 449 (1965).
Führ, J., J. Kaczmarczyk u. C. D. Krüttgen: Eine einfache Methode zur Inulinbestimmung für Nieren-Clearance-Untersuchung bei Stoffwechselgesunden und Diabetikern. Klin. Wschr. 33, 729 (1955).
Genest, J., R. Boucher, J. de Champlain, R. Veyrat, M. Chretien, P. Biron, G. Tremblay, P. Roy, and P. Cartier: Studies on the Renin-Angiotensin System in Hypertensive Patients. Canad. med. Ass. J. 90, 263 (1964).
Giebisch, G., R. M. Klose, and E. E. Windhager: Micropuncture study of hypertonic sodium chloride loading in the rat. Amer. J. Physiol. 206, 687 (1964).
Hartroft, P. M.: Juxtaglomerular cells. Circulat. Res. 12, 525 (1963).
Kramer, K.: Das akute Nierenversagen im Schock. In: Schock, Pathogenese und Therapie. Berlin, Göttingen, Heidelberg: Springer 1962.
Lassen, N. A., O. Munck, and J. H. Thaysen: Oxygen consumption and sodium reabsorption in the kidney. Acta physiol. scand. 51, 371 (1961).
Latta, H., and A. B. Maunsbach: The juxtaglomerular apparatus as studied electron microscopically. J. Ultrastruct. Res. 6, 547 (1962).
Levin, D. M., and R. Cade: Influence of dietary sodium on renal function in patients with chronic renal disease. Ann. intern. Med. 62, 231 (1965).
Leyssac, P. P.: The in vivo effect of angiotensin on the proximal tubular reabsorption of salt in rat kidneys. Acta physiol. scand. 62, 436 (1964).
Malnic, G., R. M. Klose, and G. Giebisch: Micropuncture study of renal potassium excretion in the rat. Amer. J. Physiol. 206, 674 (1964).
Munck, O.: Renal circulation in acute renal failure. Oxford: Blackwell 1958.
— N. A. Lassen, P. Deetjen, and K. Kramer: Evidence against renal hypoxia in acute hemorrhagic shock. Pflügers Arch. ges. Physiol. 274, 356 (1962).
Peter, K.: Untersuchungen über Bau und Entwicklung der Niere. Jena: 1909 und 1927.
Peters, G.: Renal tubular effect of val 5-Angiotensin amide in rats. Proc. Soc. exp. Biol. (N. Y.) 112, 771 (1963).
Phillips, R. A., and P. B. Hamilton: Effect of 20, 60, and 120 minutes of renal ischemia on glomerular and tubular function. Amer. J. Physiol. 152, 523 (1948).
Schloss, G.: Der Regulationsapparat am Gefäßpol des Nierenkörperchens in der normalen menschlichen Niere. Acta anat. (Basel) 1, 365 (1945/46).
Schröder, R., C. Meyer-Burgdorff, D. Rott u. O. Brahms: Vergleichende Untersuchungen über die Wirkung von ADH, Hypertensin und Renin auf die renale Wasser- und Elektrolytausscheidung der Ratte. Naunyn-Schmiedebergs Arch. exp. Path. Pharmak. 240, 285 (1961).
Scornik, O. A., and A. C. Paladini: Significance of blood angiotensin levels in different experimental conditions. Canad. med. Ass. J. 90, 269 (1964).
Selkurt, E. E.: Comparison of renal clearance with direct renal flow under control conditions and following renal ischemia. Amer. J. Physiol. 145, 376 (1946).
: Renal blood flow and renal clearance during hemorrhagic shock. Amer. J. Physiol. 145, 699 (1946).
Thurau, K., u. J. Schnermann: Die Natriumkonzentration an den Macula densa-Zellen als regulierender Faktor für das Glomerulumfiltrat (Mikropunktionsversuche). Klin. Wschr. 43, 410 (1965).
Ullrich, K. J., B. Schmidt-Nielsen, R. O'Dell, G. Pehling, C. W. Gottschalk, W. E. Lassiter, and M. Mylle: Micropuncture study of composition of proximal and distal tubular fluid in rat kidney. Amer. J. Physiol. 204, 527 (1963).
Vander, A. J.: Inhibition of distal tubular sodium reabsorption by angiotensin II. Amer. J. Physiol. 205, 133 (1963).
Walther, D.: Ein Beitrag zur Insuffizienz der proximalen Nierentubuli und zur Deutung der Nephrohydrose. Münch. med. Wschr. 105, 1370 (1963).
Windhager, E. E., and G. Giebisch: Micropuncture study of renal tubular transfer of sodium chloride in the rat. Amer. J. Physiol. 200, 581 (1961).
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Mit Unterstützung der Deutschen Forschungsgemeinschaft und des U.S. Department of the Army, European Research Office.
Auszugsweise vorgetragen auf der 30. Tagung (Frühjahrstagung) der Dtsch. Physiolog. Gesellschaft, Bad Nauheim 1965.
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Schnermann, J., Nagel, W. & Thurau, K. Die frühdistale Natriumkonzentration in Rattennieren nach renaler Ischämie und hämorrhagischer Hypotension. Pflügers Archiv 287, 296–310 (1966). https://doi.org/10.1007/BF00362491
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DOI: https://doi.org/10.1007/BF00362491