Transport of Adenosine by Kidney Brush Border Vesicles

2015 ◽  
pp. 417-419 ◽  
Author(s):  
M. Le Hir ◽  
U. C. Dubach ◽  
S. Angielski
Keyword(s):  
Brush Border

Scanning Electron Microscopy of Human Jejunum in Whipple's Disease

1977 ◽  
Vol 35 ◽  
pp. 354-355
Author(s):  
John H. L. Watson ◽  
C. N. Sun
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Basement Membrane ◽  
Lamina Propria ◽  
Brush Border ◽  
Whipple’S Disease ◽  
Whipple's Disease ◽  
Biopsy Specimens ◽  
Brush Borders ◽  
Scanning Electron

That the etiology of Whipple's disease could be bacterial was first suggested from electron micrographs in 1960. Evidence for binary fission of the bacteria, their phagocytosis by histiocytes in the lamina propria, their occurrence between and within the cells of the epithelium and on the brush border of the lumen were reported later. Scanning electron microscopy has been applied by us in an attempt to confirm the earlier observations by the new technique and to describe the bacterium further. Both transmission and scanning electron microscopy have been used concurrently to study the same biopsy specimens, and transmission observations have been used to confirm those made by scanning.The locations of the brush borders, the columnar epithelial cells, the basement membrane and the lamina propria beneath it were each easily identified by scanning electron microscopy. The lamina propria was completely filled with the wiener-shaped bacteria, Fig. 1.

Low-affinity transport of pyroglutamyl-histidine in renal brush-border membrane vesicles

1989 ◽  
Vol 257 (5) ◽  
pp. C971-C975 ◽  
Author(s):  
H. A. Skopicki ◽  
K. Fisher ◽  
D. Zikos ◽  
G. Flouret ◽  
D. R. Peterson
Keyword(s):  
Brush Border ◽  
Brush Border Membrane ◽  
Membrane Vesicles ◽  
Brush Border Membrane Vesicles ◽  
Proximal Tubular Cells ◽  
Tubular Cells ◽  
Luminal Membrane ◽  
Renal Brush Border Membrane ◽  
Proximal Tubular ◽  
Renal Brush Border

These studies were performed to determine if a low-affinity carrier is present in the luminal membrane of proximal tubular cells for the transport of the dipeptide, pyroglutamyl-histidine (pGlu-His). We have previously described the existence of a specific, high-affinity, low-capacity [transport constant (Kt) = 9.3 X 10(-8) M, Vmax = 6.1 X 10(-12) mol.mg-1.min-1] carrier for pGlu-His in renal brush-border membrane vesicles. In the present study, we sought to demonstrate that multiple carriers exist for the transport of a single dipeptide by determining whether a low-affinity carrier also exists for the uptake of pGlu-His. Transport of pGlu-His into brush-border membrane vesicles was saturable over the concentration range of 10(-5)-10(-3) M, yielding a Kt of 6.3 X 10(-5) M and a Vmax of 2.2 X 10(-10) mol.mg-1.min-1. Uptake was inhibited by the dipeptides glycyl-proline, glycyl-sarcosine, and carnosine but not by the tripeptide pyroglutamyl-histidyl-prolinamide. We conclude that 1) pGlu-His is transported across the luminal membrane of the proximal tubule by multiple carriers and 2) the lower affinity carrier, unlike the higher affinity carrier, is nonspecific with respect to other dipeptides.

Different diuresis-dependent excretions of urinary enzymes: N-acetyl-beta-D-glucosaminidase, alanine aminopeptidase, alkaline phosphatase, and gamma-glutamyltransferase.

1986 ◽  
Vol 32 (3) ◽  
pp. 529-532 ◽  
Author(s):  
K Jung ◽  
G Schulze ◽  
C Reinholdt
Keyword(s):  
Alkaline Phosphatase ◽  
Brush Border ◽  
Excretion Rate ◽  
Urine Flow ◽  
High Intake ◽  
Brush Border Enzymes ◽  
Urinary Creatinine ◽  
Gamma Glutamyltransferase ◽  
Alanine Aminopeptidase ◽  
Brush Border Enzyme

Abstract We studied how much of the lysosomal enzyme N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30) and of the brush-border enzymes alanine aminopeptidase (EC 3.4.11.2), alkaline phosphatase (EC 3.1.3.1), and gamma-glutamyltransferase (EC 2.3.2.2) was excreted in urine over 8 h after a high intake of fluid (22 mL per kilogram of body weight). The hourly excretion of all four enzymes increased with the increasing urine flow rate. The excretion rate of the brush-border enzymes was more markedly influenced than that of N-acetyl-beta-D-glucosaminidase. By relating the enzyme excretion to urinary creatinine we could reduce the variability of brush-border enzyme output and could completely compensate for the effect of diuresis on the excretion of N-acetyl-beta-D-glucosaminidase.

scholarly journals Characterization of cobalamin receptor sites in brush-border plasma membranes of the tapeworm Spirometra mansonoides.

1983 ◽  
Vol 258 (7) ◽  
pp. 4261-4265
Author(s):  
P A Friedman ◽  
P P Weinstein ◽  
J F Mueller ◽  
R H Allen
Keyword(s):  
Brush Border ◽  
Plasma Membranes ◽  
Receptor Sites

scholarly journals Defective brush-border expression of intrinsic factor-cobalamin receptor in canine inherited intestinal cobalamin malabsorption

1991 ◽  
Vol 266 (7) ◽  
pp. 4489-4494
Author(s):  
J C Fyfe ◽  
K S Ramanujam ◽  
K Ramaswamy ◽  
D F Patterson ◽  
B Seetharam
Keyword(s):  
Brush Border ◽  
Intrinsic Factor ◽  
Cobalamin Malabsorption
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