Alanine and Sodium Fluxes Across Mucosal Border of Rabbit Ileum

Schultz, Stanley G.; Curran, Peter F.; Chez, Ronald A.; Fuisz, Robert E.

doi:10.1085/jgp.50.5.1241

Cited by 233 publications

(120 citation statements)

References 29 publications

Supporting

Mentioning

104

Contrasting

Order By: Relevance

“…In contrast to the results of Robinson (31), our results showed a remarkable recovery (88%) by the rat small intestine, as measured with the transmural transport of 2 mM citrulline. Similar observations were made for alanine transport (32).…”

Section: Discussionsupporting

confidence: 83%

Characteristics of L-Citrulline Transport across Rat Small Intestine In Vitro

Vadgama

Evered

1992

Pediatr Res

View full text Add to dashboard Cite

ABSTRAm. The amino acid L-citrulline is an important intermediate of urea cycle and a key precursor for arginine biosynthesis. We have examined the characteristics of citrulline transport across the everted sacs of the rat small intestine. Our studies suggest that the optimal site of citrulline absorption is middle to lower ileum. It shows active transport, and this transport is predominantly Na+ dependent. Its uptake is significantly inhibited by ouabain, dinitrophenol, sodium azide, and sodium cyanide. Kinetic estimation reveal an apparent substrate concentration at % maximum velocity of 4.10 = 0.86 mM and a V,., of 18.7 f 1.66 pmol/g wet weight tissue/30 min. Analog inhibition studies suggest that citrulline may share the neutral brush border system described for the mucosal brush border membranes of the rabbit jejunum or a system analogous to system ASC described for nonepithelial cells and for basolateral membranes of certain epithelia. In conclusion, the rat small intestine has developed a specific carrier-mediated, Na+-dependent pathway for citrulline absorption.

show abstract

Section: Discussionsupporting

confidence: 83%

Characteristics of L-Citrulline Transport across Rat Small Intestine In Vitro

Vadgama

Evered

1992

Pediatr Res

View full text Add to dashboard Cite

show abstract

“…Rapid uptake of Rb, Cs, K, Na or Tl was measured by the technique of Schultz, Curran, Chez & Fuisz (1967), modified for the goldfish intestine (Ellory & Smith, 1970). The tissue is mounted and equilibrated for 25 min in an isotonic Na medium (Krebs & Henseleit, 1932) and then washed rapidly with 2 ml.…”

Section: Measurement Of Cation Nwvenents Uptake Measurementsmentioning

confidence: 99%

“…Preliminary conductance measurements were carried out in the 150 mM-NaCl medium ('Na medium') used in the uptake experiments, using a small Perspex chamber as previously described (Ellory, Evans, Heal & Smith, 1972 (Schultz et al 1967;Frizzell & Schultz, 1972;. In spite of the difference in molecular size and charge, the volume measured by choline and inulin is the same, suggesting that inulin is an adequate space marker in this preparation, and that there is no significant uptake of choline into the tissue.…”

Section: Measurement Of Tissue Conductancementioning

confidence: 99%

The effect of salt adaptation on the permeability and cation selectivity of the goldfish intestinal epithelium

Ellory¹,

Nibelle²,

Smith³

1973

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. The short-term uptake of Na by the goldfish mucosa was compared using both inulin and choline as markers of extracellular space. The results were virtually identical, the distribution of both choline and inulin increasing rapidly to measure a space at 1 min which then remained nearly constant during a following 4 min incubation.2. Using inulin as space marker, the uptake of various alkali metal cations was determined from a 1 min contact with the mucosa. The relative rates of uptake were Ti > K > Rb > Cs > Na > Li, with a low selectivity ratio, the range of permeabilities being no greater than 5. 3. The selectivity sequence was the same in both salt and fresh-water adapted fish. Of the alkali metal cations tested, only Na showed a significantly decreased uptake on adaptation to salt.4. Isolated intestinal preparations from salt-adapted fish showed a reduced short-circuit current compared with fish adapted to fresh water, the values being 12-3 + 12 and 35-7 + 1P5 ,sA cm-2 respectively. In both cases the short-circuit current was equivalent to the net transport of Na measured isotopically.5. In Krebs-Henseleit medium, the measured tissue resistance was approximately 100 Q cm-2 for both salt and fresh-water adapted fish.6. It is concluded that regulation of cation transport in goldfish intestinal epithelium is specific for Na and mediated primarily through cellular rather than extracellular pathways.

show abstract

“…The transport of neutral amino acids by rabbit ileum has been investigated extensively by Schultz, Curran, and co-workers (1)(2)(3)(4). Examination of the unidirectional fluxes of several amino acids from the mucosal solution into the cell across the brush border membrane has indicated that this influx follows Michaelis-Menten kinetics and is strongly dependent on the Na concentration in the mucosal bathing solution.…”

mentioning

confidence: 99%

Inhibition of Amino Acid Transport in Rabbit Intestine by p-Chloromercuriphenyl Sulfonic Acid

Schaeffer

Preston

Curran

1973

The Journal of General Physiology

Self Cite

View full text Add to dashboard Cite

Influx of phenylalanine across the brush border of rabbit intestine is markedly reduced by treatment with 5 mM p-chloromercuriphenyl sulfonate (PCMBS). The effect is rapidly and completely reversed by dithiothreitol. Phenylalanine influx into PCMBS-treated tissue can be competitively inhibited by other neutral amino acids and follows saturation kinetics. PCMBS causes an increase in the apparent Michaelis constant from the value observed in control tissue but does not alter the maximal influx significantly. Treatment of the tissue with PCMBS leads to a significant reduction in the Na-sensitivity of the transport, and a number of results indicate that the major effect of the reagent is to cause a marked reduction in the affinity of the transport system for Na. The transport system can be partially protected against reaction with PCMBS by phenylalanine and tryptophan but not by methionine or norleucine. The results suggest that PCMBS reacts with a sulfhydryl group in the region of the transport site and may alter conformational changes associated with the binding of substrates.

show abstract

Alanine and Sodium Fluxes Across Mucosal Border of Rabbit Ileum

Cited by 233 publications

References 29 publications

Characteristics of L-Citrulline Transport across Rat Small Intestine In Vitro

Characteristics of L-Citrulline Transport across Rat Small Intestine In Vitro

The effect of salt adaptation on the permeability and cation selectivity of the goldfish intestinal epithelium

Inhibition of Amino Acid Transport in Rabbit Intestine by p-Chloromercuriphenyl Sulfonic Acid

Contact Info

Product

Resources

About