KINETICS OF URIC ACID TRANSPORT AND ITS PRODUCTION IN RAT SMALL INTESTINE

1967 ◽  
Vol 45 (1) ◽  
pp. 121-127 ◽  
Author(s):  
Jung H. Oh ◽  
John B. Dossetor ◽  
Ivan T. Beck
Keyword(s):  
Uric Acid ◽  
Small Intestine ◽  
Intestinal Wall ◽  
The Body ◽  
Rat Small Intestine ◽  
Acid Transport ◽  
Major Site ◽  
Initial Concentration ◽  
Uricosuric Agents ◽  
Kinetics Of

Segments of the middle third of rat small intestine were incubated at 30 °C for 1 hour in the model of Crane and Wilson. When comparison was made between the uric acid contained in unincubated segments and that in both incubated segments and their incubation media, the latter was found to exceed the former nearly fivefold. This indicates that the small intestine is a major site of uric acid production in the body. The rate of uric acid-14C transport across the intestinal wall was studied with the same model, and found to be linearly proportional to its initial concentration gradient in both directions. This rate was not altered by hypoxanthine or uricosuric agents, which have been shown to influence uric acid transport in other systems. It is concluded, therefore, that uric acid transport across the wall of the small intestine is by passive diffusion.

scholarly journals Preparation, properties and metabolism of retro-3-dehydroretinyl acetate

1968 ◽  
Vol 109 (2) ◽  
pp. 293-299 ◽  
Author(s):  
A. Krishna Mallia ◽  
M. R. Lakshmanan ◽  
K. V. John ◽  
H. R. Cama
Keyword(s):  
Small Intestine ◽  
Vitamin A ◽  
Hydrobromic Acid ◽  
The Body ◽  
Rat Intestine ◽  
Retinyl Acetate ◽  
Major Site ◽  
Rat Growth ◽  
Growth Assay ◽  
Biological Potency

1. Treatment of 3-dehydroretinyl acetate with aqueous hydrobromic acid resulted in the formation of retro-3-dehydroretinyl acetate, which, on alkaline hydrolysis, gave the corresponding alcohol. 2. retro-3-Dehydroretinyl acetate was isomerized to 3-dehydrovitamin A when fed to vitamin A-deficient rats. 3. When retro-3-dehydroretinyl acetate was administered orally, it was hydrolysed to retro-3-dehydroretinol in the rat intestine, isomerized to 3-dehydroretinol and esterified before being transported to the liver for storage. 4. When administered intraperitoneally, both 3-dehydrovitamin A and retro-3-dehydrovitamin A were accumulated in liver and other tissues, whereas after enterectomy 3-dehydrovitamin A was not detected anywhere in the body. 5. The small intestine was shown to be the major site of conversion of retro-3-dehydrovitamin A into 3-dehydrovitamin A. 6. The extent of conversion of retro-3-dehydroretinyl acetate into 3-dehydrovitamin A was much smaller than that of the conversion of retro-retinyl acetate into vitamin A. 7. The biological potency of retro-3-dehydroretinyl acetate, determined by the rat-growth assay, was 2·6% of that all-trans-retinyl acetate, when given orally.

scholarly journals Metabolism of ε-(γ-L-glutamyl)-L-lysine in the rat

1975 ◽  
Vol 34 (2) ◽  
pp. 291-296 ◽  
Author(s):  
G. Raczyński ◽  
M. Snochowski ◽  
S. Buraczewski
Keyword(s):  
Small Intestine ◽  
Intestinal Wall ◽  
Rat Small Intestine ◽  
Blood Proteins ◽  
Vitro Experiment ◽  
Comparative Tests ◽  
In Vitro Experiment ◽  
Body Tissues ◽  
Everted Sacs

1. A study was made of the metabolism of ɛ-(γ-L-glutamyl)-L[4, 5-3H]lysine (GL) in the rat.2. The compound was largely absorbed from the intestine and metabolized. Labelled lysine was incorporated into blood proteins.3. In an in vitro experiment with everted sacs of rat small intestine, GL passed through the intestinal wall unchanged.4. The results of comparative tests using homogenates of different body tissues indicated that the kidneys were particularly active in hydrolysing GL. Their activity was nine times greater than that of the liver and eighteen times greater than that of the small intestine.

Kinetics of zinc transport in vitro in rat small intestine and colon: interaction with copper

2002 ◽  
Vol 16 (4-5) ◽  
pp. 289-295 ◽  
Author(s):  
Juan Condomina ◽  
Teodoro Zornoza-Sabina ◽  
Luis Granero ◽  
Ana Polache
Keyword(s):  
Small Intestine ◽  
Rat Small Intestine ◽  
Zinc Transport ◽  
Kinetics Of

scholarly journals Studies of Amino Acid Transport into Brush Border Membrane Vesicles Isolated from Rat Small Intestine

1993 ◽  
Vol 64 (7) ◽  
pp. 700-708
Author(s):  
Kiyoshi TAJIMA ◽  
Ryozo TAKADA ◽  
Toru MORI ◽  
Hisao ITABASHI ◽  
Kei-ichiro SUGIMURA
Keyword(s):  
Small Intestine ◽  
Amino Acid ◽  
Brush Border ◽  
Amino Acid Transport ◽  
Brush Border Membrane ◽  
Membrane Vesicles ◽  
Brush Border Membrane Vesicles ◽  
Rat Small Intestine ◽  
Acid Transport

Accumulation of vitamin A by small intestine of the rat in vitro

1964 ◽  
Vol 206 (2) ◽  
pp. 458-460 ◽  
Author(s):  
I. Skála ◽  
F. Hrubá
Keyword(s):  
Small Intestine ◽  
Vitamin A ◽  
Human Albumin ◽  
Intestinal Wall ◽  
Bicarbonate Buffer ◽  
Kinetics Of

The vitamin A accumulation by the small intestine of the rat was investigated, using the method of everted intestinal sacs as modified by the authors. For incubation, modified Krebs-Ringer bicarbonate buffer with vitamin A-acetate stabilized with human albumin was used. Vitamin A accumulates in the intestinal wall and the kinetics of this process are analogous to the Michaelis-Menten kinetics. Accumulation is inhibited by KCN and NaF. The transfer of vitamin A into the serosal contents of sacs was minimal. There were no significant differences in the accumulation of vitamin A in various parts of small intestine. It is concluded that the accumulation of vitamin A has a complex and active character.

scholarly journals Solubility and net exchange of calcium, magnesium and phosphorus in digesta flowing along the gut of the sheep

1975 ◽  
Vol 33 (1) ◽  
pp. 87-94 ◽  
Author(s):  
D. Ben-Ghedalia ◽  
H. Tagari ◽  
S. Zamwel ◽  
A. Bondi
Keyword(s):  
Small Intestine ◽  
Terminal Ileum ◽  
Intestinal Tract ◽  
Intestinal Wall ◽  
Major Site ◽  
Low Concentration ◽  
Calcium Magnesium ◽  
Soluble P ◽  
P Absorption

1. The changes in the solubility of calcium, magnesium and phosphorus in digesta flowing along the intestinal tract and the net movement across the intestinal wall of these elements were determined in six rams, each equipped with three T-shaped cannulas; cannulas were placed in a total of six different sites of the small intestine. Cr2O3 was used as a marker substance to measure the rate of flow of the digesta.2. The concentrations of soluble Ca, Mg and P decreased as digesta moved along the intestine. The greatest fall in soluble Ca occurred after the first 3 m of the intestine, while a significant decrease in soluble Mg was found only at 15 and 25 m from the pylorus. The concentration of soluble P in digesta decreased until the 7 m site and then remained stable. In the faeces, the level of soluble Mg was approximately 4 times higher than, and that of Ca equal to, the levels of Mg and Ca found in digesta flowing through the upper intestine. Unlike Ca and Mg, a very low concentration of soluble P was found in the faeces.3. In the duodenum, 84, 78 and 62% of the total Ca, Mg and P respectively were soluble, whereas in the digesta flowing through the terminal ileum the corresponding values were 3·2, 7·2 and 19% for Ca, Mg and P respectively.4. The forestomachs and the colon were found to be the main sites of Mg net absorption; 1·12 mmol/h was apparently absorbed from the stomach and 1·05 mmol/h from the colon. The upper small intestine (1–3 m from the pylorus) appeared to be the major site of Ca and P absorption.5. In the last 10 m of the small intestine, considerable amounts of minerals were secreted; 4·70, 0·96 and 1·85 mmol Ca, Mg and P/h respectively were added to the digesta flowing between 15 and 25 m from the pylorus. The effect of the increase in the pH of digesta along the small intestine on the solubility of these minerals is discussed.

Sign in / Sign up

Export Citation Format

Share Document