Ouabain-insensitive active sodium transport in rat jejunum: Evidence from ATPase activities, Na uptake by basolateral membrane vesicles andin vitro transintestinal transport

1988 ◽  
Vol 6 (3) ◽  
pp. 155-164 ◽  
Author(s):  
M. Tosco ◽  
M. N. Orsenigo ◽  
G. Esposito ◽  
A. Faelli
Keyword(s):  
Sodium Transport ◽  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Rat Jejunum ◽  
Basolateral Membrane Vesicles ◽  
Active Sodium ◽  
Active Sodium Transport ◽  
Na Uptake

Bicarbonate uptake by basolateral membrane vesicles from rat jejunum

1983 ◽  
Vol 91 (5) ◽  
pp. 423-432
Author(s):  
A. Faelli ◽  
M. Tosco ◽  
M. N. Orsenigo ◽  
G. Esposito ◽  
V. Capraro
Keyword(s):  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Rat Jejunum ◽  
Basolateral Membrane Vesicles ◽  
Bicarbonate Uptake

Proton-lactate co transport in basolateral membrane vesicles from rat jejunum

1996 ◽  
Vol 16 (6) ◽  
pp. 521-527
Author(s):  
Maria Novella Orsenigo ◽  
Marisa Tosco ◽  
Umberto Laforenza ◽  
Alide Faelli
Keyword(s):  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Rat Jejunum ◽  
Basolateral Membrane Vesicles ◽  
Strong Inhibition ◽  
Lactate Transport ◽  
Basolateral Membranes ◽  
Lactate Uptake ◽  
Stimulation Of

Proton-coupled lactate transport across the basolateral membrane of rat jejunal enterocyte was studied using well purified membrane vesicles. L-lactate uptake is stimulated by an inwardly directed H+ gradient; the effect of the pH difference is drastically reduced by FCCP and by pCMBS; unlabelled L-lactate causes a strong inhibition, whilst furosemide is uneffective. The H+ gradient-dependent stimulation of L-lactate uptake is significantly inhibited also by SCN−: this finding could explain results recently reported in the literature in which H+-lactate symport was not evidenced in basolateral membranes from rat jejunum.

Pathways for HCO 3 − exit across the basolateral membrane in rat thick limbs

1999 ◽  
Vol 276 (6) ◽  
pp. F847-F856 ◽  
Author(s):  
Françoise Leviel ◽  
Dominique Eladari ◽  
Anne Blanchard ◽  
Jean-Stéphane Poumarat ◽  
Michel Paillard ◽  
...  
Keyword(s):  
Intracellular Ph ◽  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
The Other ◽  
Ph Gradient ◽  
Basolateral Membrane Vesicles ◽  
Positive Potential ◽  
Major Pathway ◽  
Stilbene Derivative ◽  
Na Uptake

We studied the pathways for [Formula: see text] transport in basolateral membrane vesicles (BLMV) purified from rat medullary thick ascending limbs (MTAL). An inward [Formula: see text]gradient in the presence of an inside-positive potential stimulated the rate of 22Na uptake minimally and did not induce a 22Na overshoot, arguing against the presence of electrogenic Na+-[Formula: see text]cotransport in these membranes. An inside-acid pH gradient stimulated to the same degree uptake of86Rb+(a K+ analog) with or without[Formula: see text]. Conversely, applying an outward K+ gradient caused a modest intracellular pH (pHi) decrease of ∼0.38 pH units/min, as monitored by quenching of carboxyfluorescein; its rate was unaffected by[Formula: see text], indicating the absence of appreciable K+-[Formula: see text]cotransport. On the other hand, imposing an inward Cl− gradient in the presence of [Formula: see text] caused a marked pHi decrease of ∼1.68 pH units/min; its rate was inhibited by a stilbene derivative. Finally, we could not demonstrate the presence of a[Formula: see text]/lactate exchanger in BLMV. In conclusion, the presence of significant Na+-, K+-, or lactate-linked[Formula: see text] transport could not be demonstrated. These and other data suggest that basolateral Cl−/[Formula: see text]exchange could be the major pathway for[Formula: see text] transport in the MTAL.

Na+-H+ antiporter of rat colonic basolateral membrane vesicles

1989 ◽  
Vol 257 (4) ◽  
pp. G624-G632 ◽  
Author(s):  
P. K. Dudeja ◽  
E. S. Foster ◽  
T. A. Brasitus
Keyword(s):  
Exchange Process ◽  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Disulfonic Acid ◽  
Basolateral Membrane Vesicles ◽  
Proton Efflux ◽  
Sodium Gradient ◽  
Transport Inhibitors ◽  
22Na Uptake ◽  
Na Uptake

The present experiments were conducted, using acridine orange and 22Na uptake techniques, to demonstrate the presence of an electroneutral Na+-H+ exchange process in rat colonic basolateral membrane vesicles. Results consistent with the existence of a distinct Na+-H+ antiporter in these vesicles include the following: 1) an outwardly directed Na+ gradient stimulated proton influx (Na+in, 100 mM; pHin 7.5/pHout 7.5) and an inwardly directed sodium gradient (Na+out, 5-50 mM; pHin 6.0/pHout 7.5) stimulated proton efflux; 2) sodium-stimulated proton influx was minimally decreased (approximately 10-25%) under voltage clamp conditions (addition of valinomycin in the presence of K+ on both sides of vesicles), indicating that Na+ for H+ exchange in these vesicles could not be explained solely on the basis of a membrane potential; 3) an outwardly directed proton gradient (pHin 5.5/pHout 7.5) stimulated 22Na uptake into these vesicles and a threefold "over-shoot" was observed; 4) 22Na uptake and sodium-stimulated proton efflux were saturable with a Km for Na+ of 5.8 +/- 0.9 and 7.0 +/- 0.3 mM, respectively; 5) amiloride (1 mM) significantly inhibited both sodium-stimulated proton efflux (approximately 69%) and 22Na uptake (approximately 89%), but other transport inhibitors (acetazolamide, 4-acetamido-4'isothiocyanostilbene-2,2'-disulfonic acid, and bumetanide) had no effect on 22Na uptake; 6) N-methylglucamine+ (a nonpermeant cation) did not affect pH gradient-stimulated 22Na uptake, whereas Li+ inhibited Na+ uptake; 7) an inwardly directed Li+ gradient stimulated proton efflux and the Km for Li+ was 12.5 +/- 1.5 mM. These findings establish the existence of an electroneutral Na+-H+ exchange mechanism in rat colonic basolateral membrane vesicles.

Bicarbonate movement across basolateral membrane vesicles from rat jejunum

1984 ◽  
Vol 401 (4) ◽  
pp. 427-429
Author(s):  
A. Faelli ◽  
M. Tosco ◽  
M. N. Orsenigo ◽  
G. Esposito ◽  
V. Capraro
Keyword(s):  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Rat Jejunum ◽  
Basolateral Membrane Vesicles

The effect of GIP and glucagon-like peptides on intestinal basolateral membrane hexose transport

1996 ◽  
Vol 271 (3) ◽  
pp. G477-G482 ◽  
Author(s):  
C. I. Cheeseman ◽  
R. Tsang
Keyword(s):  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Gastric Inhibitory Polypeptide ◽  
Transport Rate ◽  
Rat Jejunum ◽  
Hexose Transport ◽  
Basolateral Membrane Vesicles ◽  
Pentobarbital Sodium ◽  
Luminal Perfusion ◽  
Pentobarbital Sodium Anesthesia

The effect of gastric inhibitory polypeptide (GIP) and the related glucagon-like peptides-1 and -2 (GLP-1 and GLP-2) on jejunal basolateral membrane glucose transport was investigated to determine if the upregulation produced by luminal hexoses could be explained by the release of one or more of these peptides. Luminal perfusion of the rat jejunum for 4 h, under pentobarbital sodium anesthesia, with 100 mM D-glucose produced a significant increase in plasma GIP levels. Vascular infusion of saline containing 100-800 pM GIP also increased the maximal transport rate for carrier-mediated glucose uptake in jejunal basolateral membrane vesicles. The effect of vascular 400 pM GIP was maximal after 1 h and maintained out to 4 h. The effect of luminal glucose could be blocked by preinjection with anti-GIP antibodies, whereas an antineurotensin antibody had no effect. Vascular infusion with 800 pM GLP-1-(7-36) amide had no effect, but GLP-2 (400 and 800 pM) increased the D-glucose maximal transport rate. An anti-GLP antibody was able to block the response to luminal glucose.

Sodium transport in human intestinal basolateral membrane vesicles

1992 ◽  
Vol 103 (6) ◽  
pp. 1817-1822 ◽  
Author(s):  
Zafar Zamir ◽  
Jeanne A. Barry ◽  
Krishnamurthy Ramaswamy
Keyword(s):  
Sodium Transport ◽  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Basolateral Membrane Vesicles

Inhibition of active sodium transport by cytochalasin B in rat jejunum in vitro

1983 ◽  
Vol 763 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Paula T. Beall ◽  
Karl J. Karnaky ◽  
Leon T. Garretson ◽  
Yuh-Jyh Kuo ◽  
Linda L. Shanbour
Keyword(s):  
Sodium Transport ◽  
Cytochalasin B ◽  
Rat Jejunum ◽  
Active Sodium ◽  
Active Sodium Transport
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