Summary:The catalytic activities of alkaline phosphatase and N-acetyl-ß-Z>-glucosaminidase, constituents of luminal bnish-border membranes and lysosomes of kidney tubular cells, were measured in human kidney allografts in the mäintenance and recovery phases of acute renal failure and in acute rejection crisis. The enzyme activities were fluorometrically determined in single microdissected cortical nephron Segments of biopsies from 4 kidney allografts taken intraoperatively and postoperatively at different periods, which exhibited either goöd function or dysfunction. For comparison, the unaffected part of a human kidney nephrectomized due to hypernephroma äs well äs a biopsy of a morphologically normal human kidney were examined.Both enzymes displayed highest activities in the proximal part of the human nephron. In some intraoperative and ppstoperätive biopsies with acute renal failure, alkaline phosphatase activity was reduced in proximal tubules, predominantly in the straight portion. This reduction could not be correlated with function. In acute rejection, very low alkaline phosphatase activities were uniformly found in proximal convoluted and straight tubules. Fürthermore, intraoperative biopsies and biopsies of the functioning allograft have only approximately 50% of normal N-acetyl-ß-D-glucosaminidase activity in proximal convoluted tubules, but generally normal values in the straight portion. However, in acute renal failure, this enzyme activity was several-fold enhanced along the whole nephron, when compared with intraoperative values. In acute rejection, N-acetyl-ß-jp-glucpsaminidase activity was slightly reduced in proximal convoluted tubules, when compared with biopsies showing gööd function.It is suggested that the decrease of proximal tubular enzyme activities is the consequence of increased enzymuria and inadequate enzyme regeneration. On the other hand, the overshoot of N-acetyl-ß-/)-glucosamißidase activity in the maintenance phase of acute renal failure appears to indicate increased degradative capacity, associated with cellular regeneration along the whole nephron. Schmid, Mall and Bockhorn: Enzyme activities in human kidney ailografts with impaired function Kataly tische Aktivitäten von alkalischer Phosphatase undN-Acetyl-ß-D-glucosaminidase in menschlichen corticalen Nephronsegmenten: Heterogene Veränderungen bei akutem Nierenversagen und akuter Abstoßung nach NierentransplantationZusammenfassung: Die katalytischen Aktivitäten von alkalischer Phosphatase und N-Acetyl-ß-Z>-glucosaminidase, Bestandteilen von luminalen Bürstensaum-Membranen und Lysosomen der Nierentubulus-Zellen, wurden in menschlichen Nierentransplantaten in Spät-und Erholungsphase akuten Nierenversagens und bei akuter Abstoßungskrise gemessen. Die Enzymaktivitäten wurden fluorometrisch in einzelne^mikrodissezier-ten corticalen Nephronsegmenten von Biopsien aus 4 Nierentransplantaten bestimmt, die intraoperativ und postoperativ zu verschiedenen Zeiten bei guter oder schlechter Funktion gewonnen wurden. Zum Vergleich wurden der n...

The glycolytic capacity in rat kidney was studied under conditions of stimulated gluconeogenesis like 48 h starvation and 48 h acidosis induced by force-feeding with a NH4Cl/glucose solution. Rats fed ad libitum and force-fed with a glucose solution served as controls. The specific activities of the key enzymes phosphofructokinase and pyruvate kinase were determined in single segments of the nephron. The determinations were performed by microdissection of lyophilized tissue sections followed by enzymatic analysis, including oil well technique, enzymatic amplification, and fluorometric measurement.In the distal portion of the nephron of both fed and force-fed animals a 10-fold higher specific activity of phosphofructokinase and pyruvate kinase was found compared with the proximal portion, known as the site of renal gluconeogenesis. Starvation and acidosis altered neither the distribution pattern nor the specific activities of these enzymes.From these results it is concluded that renal glycolysis does not undergo alterations at the level of enzymatic activities in favour of renal gluconeogenesis, probably because of the separate localization of both pathways within the nephron.

Summary:The catalytic activities of Na+-K + -ATPase and succinate dehydrogenase, marker enzymes for active salt reabsorptive capacity of renal basolateral plasma membranes and for respiratory capacity of mitochondrial cristae membranes, were studied in the maintenance phase of human acute post-transplant renal failure. Biopsies of 4 kidney-allografts taken at transplantation Operation and additionally at different posttransplantation periods, either with good function or in various stages of dysfunction, were compared with the unaffected part of a human kidney nephrectomized due to hypernephroma. In single nephron segments, Na + -K + -ATPase activity was determined after microdissection by microfluorometry, and succinate dehydrogenase activity was determined by a microphotometric procedure in stained cryosections.In intraoperative and postoperative biopsies of a well-functioning allograft, both Na + -K + -ATPase and succinate dehydrogenase activities did not differ from those of normal renal tissue. In contrast, the catalytic activities were found to be decfeased in the distal tubules of 2 anüric allografts when compared with their intraoperative controls. In addition, succinate dehydrogenase activity was reduced in distal tubules of a recovering allograft. Catalytic activities appeared to be unaffected in glomeruli, proximal tubules, and collecting ducts.It is suggested that the predominant distal tubular alterations with regard to these parameters are a consequence of increased distal tubular vulnerability due to circulatory and metabolic conditions. Verändertes Verteilungsmuster der Na + -K+-ATPase-und Succinat-Dehydrogenase-Aktivitäten entlang des Nephrons bei akutem Nierenversagen nach Nierentransplantation beim MenschenZusammenfassung: Die katalytischen Aktivitäten von Na der Erholungsphase war die Succinat-Dehydrogenase-Aktivität ebenfalls vermindert. In den Glomeruli, proximalen Tubuli und Sammelrohren wurden unveränderte katalytische Aktivitäten gemessen.Die bezüglich dieser Kenngrößen vorwiegend distal lokalisierten tubulären Veränderungen sind als Folge einer größeren Vulnerabilität dieser Nephronabschnitte auf Grund der Durchblutungs-und Stoffwechselverhältnisse anzusehen.

The clinical findings and past history with regard to bacterial urinary infection were correlated with the morbid-anatomical findings in 51 cases of analgesic nephropathy, confirmed clinically and histologically. Light-microscopy and immunohistology indicated that clinical and morphological findings agreed in 64.7%. In 23.5% of cases there was evidence of destruction without any history of urinary tract infection, while in 11.8% there was no destruction even after urinary tract infections. Clinical findings and morphological results were thus complementary in that the incidence of bacterial urinary tract infection with renal involvement was definitely higher in analgesic nephropathy than on isolated assessment by clinical means or histology alone.

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