Ca-stimulated ATPase in brush border and basolateral membranes of rat duodenum with high affinity sites for Ca ions

Nature ◽  
1979 ◽  
Vol 279 (5716) ◽  
pp. 802-803 ◽  
Author(s):  
W. E. J. M. GHIJSEN ◽  
C. H. VAN Os
Keyword(s):  
Brush Border ◽  
Basolateral Membranes ◽  
High Affinity ◽  
Rat Duodenum ◽  
Ca Ions

Subcellular distribution of nucleotide cyclases in rat intestinal epithelium.

1978 ◽  
Vol 235 (5) ◽  
pp. E539 ◽  
Author(s):  
M W Walling ◽  
A K Mircheff ◽  
C H Van Os ◽  
E M Wright
Keyword(s):  
Adenylate Cyclase ◽  
Guanylate Cyclase ◽  
Brush Border ◽  
Linear Regression Analysis ◽  
Basolateral Membrane ◽  
Multiple Linear Regression Analysis ◽  
Isolated Cells ◽  
Basolateral Membranes ◽  
Rat Duodenum ◽  
Triton X

The subcellular distributions of adenylate cyclase and guanylate cyclase were determined for the mature enterocyte from the rat duodenum. Brush-border and basolateral membranes were prepared from isolated cells by an analytical isolation procedure, and multiple linear regression analysis was used to obtain a quantitative estimate of the distribution of recovered cyclase activities between the brush borders and basolateral membranes. Adenylate cyclase was largely confined to the basolateral surface of the epithelium, whereas guanylate cyclase was found on the brush-border and basolateral membrane fractions in the ratio 2.4:1. There was no evidence for the presence of nucleotide cyclases in the cytosol. Guanylate cyclase in both the brush-border and basolateral membranes was stimulated by epinephrine, insulin, and Triton X-100, but not by carbachol. Adenylate cyclase was not influenced by epinephrine, but was markedly stimulated by NaF and vasoactive intestinal peptide. These results are discussed in relation to the effects of hormones on transport across the small intestine.

scholarly journals Characterization of calcium binding to brush-border membranes from rat duodenum

1982 ◽  
Vol 208 (3) ◽  
pp. 773-781 ◽  
Author(s):  
A Miller ◽  
S T Li ◽  
F Bronner
Keyword(s):  
Brush Border ◽  
Binding Sites ◽  
Calcium Binding ◽  
Specific Binding ◽  
Relative Effectiveness ◽  
Brush Border Membranes ◽  
High Affinity ◽  
High Affinity Site ◽  
Rat Duodenum ◽  
High Concentrations

The Ca2+-binding properties of isolated brush-border membranes at physiological ionic strength and pH were examined by rapid Millipore filtration. A comprehensive analysis of the binding data suggested the presence of two types of Ca2+-binding sites. The high-affinity sites, Ka = (6.3 +/- 3.3) X 10(5) M-1 (mean +/- S.E.M.), bound 0.8 +/- 0.1 nmol of Ca2+/mg of protein and the low-affinity sites, Ka = (2.8 +/- 0.3) X 10(2) M-1, bound 33 +/- 3.5 nmol of Ca2+/mg of protein. The high-affinity site exhibited a selectivity for Ca2+, since high concentrations of competing bivalent cations were required to inhibit Ca2+ binding. The relative effectiveness of the competing cations (1 and 10 mM) for the high-affinity site was Mn2+ approximately equal to Sr2+ greater than Ba2+ greater than Mg2+. Data from the pH studies, treatment of the membranes with carbodi-imide and extraction of phospholipids with aqueous acetone and NH3 provided evidence that the low-affinity sites were primarily phospholipids and the high-affinity sites were either phosphoprotein or protein with associated phospholipid. Two possible roles for the high-affinity binding sites are suggested. Either high-affinity Ca2+ binding is involved with specific enzyme activities or Ca2+ transport across the luminal membrane occurs via a Ca2+ channel which contains a high-affinity Ca2+-specific binding site that may regulate the intracellular Ca2+ concentration and gating of the channel.

Effect of meleate on membrane physical state of brush border and basolateral membranes of the dog kidney

Life Sciences ◽  
1982 ◽  
Vol 30 (13) ◽  
pp. 1107-1111 ◽  
Author(s):  
Christian Le Grimellec ◽  
Serge Carrière ◽  
Jean Cardinal ◽  
Marie-Cécile Giocondi
Keyword(s):  
Brush Border ◽  
Physical State ◽  
Basolateral Membranes ◽  
Dog Kidney

Membrane fluidity and enzyme activities in brush border and basolateral membranes of the dog kidney

1982 ◽  
Vol 242 (3) ◽  
pp. F246-F253 ◽  
Author(s):  
C. Le Grimellec ◽  
M. C. Giocondi ◽  
B. Carriere ◽  
S. Carriere ◽  
J. Cardinal
Keyword(s):  
Alkaline Phosphatase ◽  
Brush Border ◽  
Plasma Membranes ◽  
Physical State ◽  
Arrhenius Plot ◽  
Membrane Lipids ◽  
Basolateral Membranes ◽  
Brush Border Membranes ◽  
Dog Kidney ◽  
Additional Support

The physical state of membrane lipids and relationships with the activity of Na+-K+-ATPase and alkaline phosphatase were studied in basolateral and brush border membranes of the dog kidney. Fluorescence polarization and electron spin resonance experiments demonstrate that basolateral membranes are much more fluid than brush border membranes. This can be accounted for by a difference in fluidity of the lipid part of the membranes. Broad (43-17 degrees C) thermotropic transitions are observed in liposomes made from total lipid extracts of brush border and basolateral membranes. Fluorescence data strongly suggest that thermotropic transitions also occur in intact membranes and that a change in membrane physical state may take place around the physiological temperature. A nonlinear Arrhenius plot for the Na+-K+-ATPase activity in basolateral membranes (breakpoint 21 degrees C) provides additional support for the existence of a lipid liquid leads to gel transition in antiluminal plasma membranes. A break in the Arrhenius plot of alkaline phosphatase activity is also observed but at a temperature significantly higher (26 degrees C) than that of the end of the thermotropic transition. "Room temperature" appears as a critical zone for lipid physical state and activities of both enzymes.

Uphill transport of beta-alanine in intestinal brush-border membrane vesicles

1990 ◽  
Vol 259 (3) ◽  
pp. G372-G379 ◽  
Author(s):  
Y. Miyamoto ◽  
H. Nakamura ◽  
T. Hoshi ◽  
V. Ganapathy ◽  
F. H. Leibach
Keyword(s):  
Brush Border ◽  
Brush Border Membrane ◽  
Membrane Vesicles ◽  
Brush Border Membrane Vesicles ◽  
Beta Alanine ◽  
Intestinal Brush Border Membrane ◽  
High Affinity ◽  
Intestinal Brush Border ◽  
Proximal Small Intestine ◽  
Uptake Process

The characteristics of beta-alaline uptake were studied in brush-border membrane vesicles isolated from the proximal small intestine of rabbits and were compared with those of L-alpha-alanine uptake. The uptake of beta-alanine as well as L-alpha-alanine was significantly stimulated by imposing an inwardly directed Na+ gradient. Studies on transstimulation and substrate specificity provide evidence that the transport system serving beta-alanine is distinct from the system serving alpha-alanine. The beta-system also accepts taurine as a substrate. The Na(+)-dependent uptakes of beta-alanine and L-alpha-alanine were differentially influenced by anions. The order in which anions supported uptake was Cl- = SCN- greater than F- greater than NO3- = SO2(-4) for beta-alanine, whereas it was SCN- greater than F- = Cl- = NO3- greater than SO2(-4) for L-alpha-alanine. Cl- appeared to be the preferred anion to support the uptake of beta-alanine. beta-Alanine uptake was greater in the presence of an inwardly directed Cl- gradient than in the presence of Cl- at equal concentrations on both sides of the membrane. The uptake was maximal when a Na+ gradient and a Cl- gradient were present simultaneously. The NaCl gradient-driven beta-alanine uptake was stimulated by an inside-negative K(+)-diffusion potential induced by valinomycin, showing that the uptake process is electrogenic. Stoichiometric analyses suggest that multiple Na+ and one Cl- are associated with the uptake of one beta-alanine molecule. The kinetic study shows that the transporter for beta-alanine is a high-affinity, low-capacity system (Kt = 46 +/- 1 microM; Vmax = 30 +/- 1 pmol.mg protein-1.15 s-1).

D-glucose and L-leucine transport by human intestinal brush-border membrane vesicles

1989 ◽  
Vol 256 (3) ◽  
pp. G618-G623 ◽  
Author(s):  
J. M. Harig ◽  
J. A. Barry ◽  
V. M. Rajendran ◽  
K. H. Soergel ◽  
K. Ramaswamy
Keyword(s):  
Small Intestine ◽  
Brush Border ◽  
Brush Border Membrane ◽  
Membrane Vesicles ◽  
Brush Border Membrane Vesicles ◽  
Transport Systems ◽  
Intestinal Brush Border Membrane ◽  
High Affinity ◽  
Intestinal Brush Border ◽  
Sodium Gradient

This study utilized intestinal brush-border membrane vesicles obtained from organ donor intestine to characterize the absorption of D-glucose and L-leucine in the human intestine. Both D-glucose and L-leucine were taken up by sodium gradient-dependent active transport along the entire length of the small intestine. The relative magnitude of transport for both substrates under sodium gradient conditions followed the order distal jejunum greater than proximal jejunum greater than distal ileum. The number of carrier systems in these brush-border membrane vesicles was estimated by Eadie-Hofstee plot analysis. This analysis revealed that L-leucine was actively transported via a single high-affinity transport system for the length of the human small intestine. In contrast, the transport of D-glucose occurred via a high-affinity system along the length of the intestine and via a low-affinity, high-flux transport system that was limited to the proximal intestine. Both glucose transport systems were sodium dependent and phlorizin sensitive. The locations and apparent kinetic parameters of these transport systems indicated that these systems function efficiently in vivo as important mechanisms for carbohydrate and protein assimilation in humans. The presence of these active transport systems along the entire small intestine explains the formidable capacity for carbohydrate and protein assimilation in humans.

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