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PubMed1981

[Isolation and study of the properties of the catalytic subunit of cAMP-dependent protein kinase of the small intestinal mucosa of the rabbit].

cAMP-dependent and casein proteinkinase were found in cytosol of the rabbit small intestine mucosa. cAMP-dependent proteinkinase of cytosol is represented by two forms of types I and II. The activity of enzymes of types I and II constitutes 10 and 90%, respectively. Casein proteinkinase is represented by a single form. The catalytic subunit of cAMP-dependent proteinkinase of type II was isolated in a homogenous state. The catalytic subunit phosphorylates histones H1, H2a, H2b and protamine and to a far less degree histones H3, H4 and casein (H2b greater than H1 greater than H2a greater than protamine much greater than H3 greater than casein). The Km value for histone H1 is equal to 65 mkM, and that for Mg-ATP 12 mkM. Chloromethylpyrophosphonate and adenosine p-fluorosulfobenzoate were studied as affine modifiers of the active center of the catalytic subunit from the small intestine mucosa. It was shown that only adenosine p-fluorosulfonate is an irreversible inhibitor of the catalytic subunit.

Animals↗

PubMed1980

[Quantitative investigations of the structure and function of the intestinal mucosa in endoscopically obtained biopsy material. Findings in patients with coeliac disease, patients with partially resected small intestine in Crohn's disease and in patients with small intestine resection for other reasons (author's transl)].

During an endoscopy of the upper gastrointestinal tract, biopsy material of the small intestine was obtained and structure and function of the small intestinal mucosa was investigated. The data were then compared with published results, gained by normally performed blind biopsy techniques. For that the findings of three groups of patients (1. patients with coeliac disease [9], 2, patients with ileal resection due to ileitis terminalis Crohn [9], 3. patients with partially resection of the small intestine due to other reasons [4]) were compared with healthy controls (10). The results indicate that obtaining small intestinal biopsy material endoscopically enables a valid characterization of differentiated properties of the small bowel mucosa. The data of the patients with coeliac disease are in complete agreement with the criteria of this syndrome, published in the literature. On the other hand the results of the group with partial resection of the small intestine resection (without chronic inflammatory bowel disease) show all signs of adaptive mucosal hyperplasia of the remaining small intestine. However, patients with Crohn's disease did not show any adaptive response to small bowel resection.

Adaptation, Physiological↗

PubMed2003

Long chain fatty acid uptake by human intestinal mucosa in vitro: mechanisms of transport.

BACKGROUND/AIMS: The aim of this study was to investigate whether a carrier-mediated membrane transport for long chain fatty acid (LCFA) exists in the human intestinal mucosa. METHODS: Biopsies obtained from the small intestine of patients, during routine endoscopies, were incubated for different periods in the presence of [(3)H]oleic acid complexed to albumin, and lipid fractions were separated and quantified. Biopsies were also incubated during 5 min in different oleic acid:albumin molar ratios. The effect of temperature on lipid transport was tested by incubating biopsies at 37 and 4 degrees C. RESULTS: Maximum [(3)H]oleic acid uptake occurred at 15 min. With increasing unbound oleic acid concentrations in the medium, LCFA uptake during 5 min of incubation revealed a typical saturation kinetics profile, and exhibiting apparent K(m) values of 3.43 +/- 0.83 microM, and apparent V(max) values of 0.86 +/- 0.07 nmol x min(-1) x mg(-1). Within this period, nearly all intracellular fatty acid remained in the unesterified form. The system was also temperature-dependent, having shown a significant reduction of 78.03% in [(3)H]oleic acid uptake at 4 degrees C, in 5 min of incubation. CONCLUSIONS: Our data confirm that LCFA uptake by human intestinal mucosa is likely to occur via a saturable carrier.

Adult↗

PubMed1986

[Mastocytes in the human intestinal mucosa].

A method has been for counting the mastocytes on 0.1 mm2 of intestinal mucosa in patients with chronic enterocolitis, gluten enteropathy, ulcerous colitis in a stage of exacerbation and in controls. The comparison of the results obtained in the separate groups of patients reveal an increased number of mastocytes in gluten enteropathy--mean = 21.01 +/- 6 as compared with the chronic enterocolitis, where mean = 9.79 +/- 3.83 (p = 0.002). Higher values of mastocytes in rectal mucosa were observed in the patients with ulcerous mucosa--mean = 15.83 +/- 4.49 as compared with the control subjects with means = 3.67 +/- 0.99 (p = 0.001). those data admit the participation of mastocytes in the morbid process in patients with gluten enteropathy and with ulcerous colitis.

Biopsy↗

PubMed1984

Quantitative analysis of small intestinal mucosa in cow's milk-sensitive enteropathy.

The appearance of the small intestinal mucosa in cow's milk protein intolerance (CMPI) was studied using quantitative morphometry. The parameters under study were the numbers of eosinophil cells in the lamina propria and epithelium, villous height, crypt zone depth, villous height/crypt zone depth ratio, and total mucosal thickness. Tracings of whole sections were analysed using a suitably programmed minicomputer linked to a digitising table. Small bowel biopsy specimens from children with untreated CMPI, from children before and after clinical relapse on cow's milk challenges, and from children with resolved CMPI were compared to each other, to those from control infants, and to those from children with coeliac disease. No change of diagnostic significance could be found in the number of lamina propria eosinophil cells, but levels of intraepithelial eosinophils were significantly increased following cow's milk challenge. Quantification of mucosal dimensions confirmed the presence of a cow's milk-sensitive enteropathy and established the finding of a thin mucosa in CMPI regardless of clinical disease activity. Mucosal thickness was not different from control values following resolution of the disease. In coeliac disease mucosal thickness was significantly greater than in CMPI (apart from young children with untreated coeliac disease whose mucosa was not thicker than that of children with untreated CMPI) but not different from control values. It is suggested that in CMPI there is a limitation in the capacity of crypt cells to compensate for the loss of villous epithelium.

Biopsy↗

PubMed1989

[Experimental studies of the small intestine mucosa].

The problems pertaining to the surgical therapy of the short bowel syndrome have not yet been solved despite numerous methods for the retardation of stool passage and the enlargement of the absorbent small intestinal surface. We therefore developed a model for the cultivation of neomucosa of endogenous origin on the perietal peritoneum of Wistar rats. In 191 young Wistar rats of each sex with a body weight of 200 to 500 grams, a loop of the small intestine was largely blocked off from the intestine with the help of Braun's anastomosis, opened up and thus sewed onto the parietal peritoneum of the laboratory animal. This led to the formation of a tube with two-thirds of the circumference consisting of small intestine and one-third of peritoneum. After the peritoneal part had been over-grown by neomucosa, the original jejunal part was removed and a tube consisting of perietal peritoneum with a muscular portion was formed around the neomucosal island. After another 4-5 months, a mucosal tube with complete neomucosal lining had formed. It was demonstrated by histological, enzyme histochemical and electron microscopy methods that the neomucosa is indeed a functioning small intestinal mucosa. Intragastric administration of a prostaglandin E2 analogue resulted in accelerated neomucosal growth as well as an increase in the height of the villi and the depth of the cryptae and a decrease in the thickness of the granular tissue. Measurements of the accumulation of 14C glucose and its inhibition by ouabain confirmed the active transport of the 14C glucose in the cell of the small intestinal neomucosa. The cultivation of functioning small intestinal mucosa on the perietal peritoneum of rats was thus accomplished.

Animals↗

PubMed1987

Effect of level of alimentation on visceral organ mass and the morphology and Na+, K+ adenosinetriphosphatase activity of intestinal mucosa in lambs.

Changes in ovine visceral organ mass and small intestinal mucosa morphology and metabolism due to short-term and prolonged modifications in level of alimentation were studied. Thirty-six lambs were fed for 21 d at either 100 or 50% ad libitum levels of intake. For the next 5 d, lambs either remained on the same intake levels or were switched from 100 or 50% or from 50 to 100% ad libitum intake levels and were subsequently slaughtered. Levels of alimentation the last 5 d before slaughter had a significant effect on weights of the large intestine, small intestine, stomach complex and liver, while only the weight of the liver was affected by 21-d adaptation period. Weights of the heart, lungs, carcass and visceral fat were not affected by level of alimentation. Villus height and mucosal mass at a constant intestinal tissue weight were modified by level of alimentation 5 d before slaughter but static to the previous 21-d nutritional plane. Activity of Na+, K+ ATPase of jejunal mucosa was not influenced by level of alimentation 5 d before slaughter, but was influenced by 21-d adapted level of alimentation. Results from this study are interpreted to indicate that weights of the liver and alimentary tract and small intestinal mucosa development are highly sensitive to changes in level of alimentation.

Animal Nutritional Physiological Phenomena↗

PubMed1986

A novel, simple and rapid method for the isolation of mitochondria which exhibit respiratory control, from rat small intestinal mucosa.

A method is described for the isolation of functional mitochondria from rat intestinal mucosa. Its novel feature is the removal of mucus from the initial homogenate by treatment with DEAE-cellulose. The preparations exhibited acceptable ADP:O ratios, high State-3 respiration rates, and respiratory control ratios in excess of 3 when succinate, beta-hydroxybutyrate, glutamate/malate and glutamine were test substrates.

Animals↗

PubMed1983

[Functional state of the mitochondria of the small intestine mucosa during heat stress].

Rate of respiration and effectiveness of oxidative phosphorylation of intestinal mucosa mitochondria in rats revealed that adaptation to heat loads is accompanied by reversible switching over of the NAD-dependent and succinate ways of mitochondria oxygenation which maintains the normal existence of mucosal cells in conditions of heat stress. Severe heat stress disturbs the functional integrity of the oxygenation switching over and leads to disturbances of the rate of oxygenation and effectiveness of oxidative phosphorylation.

Adaptation, Physiological↗

PubMed1977

Effect of vitamin A nutritional status on the ribonucleic acids of liver, intestinal mucosa and testes of rats.

1. Vitamin A deficiency led to an increase in the oligonucleotide fraction of testes and intestinal mucosa of rats at the expense of high-molecular-weight RNA and 4S RNA, but no such changes were observed in the liver. Retinyl acetate supplementation reversed these effects in both tissues, whereas retinoic acid supplementation was almost equally effective in the mucosa but virtually ineffective in the testes. The ribonuclease activities of all the tissues remained unaffected by the above treatments. 2. The effect of vitamin A deprivation on the acceptor activity of the tRNA of the testes and intestinal mucosa was more pronounced than on the liver tRNA. The testes and mucosal tRNA of the retinoic acid-supplemented rats showed significantly lower charging capacity as compared with the retinyl acetate-supplemented ones. Here also no significant effect was observed on the liver tRNA. 3. Vitamin A deficiency caused a decrease in the percentage of poly(A) in RNA of the mucosa and testes, but not in the liver RNA. The poly(A) contents of both tissues were brought to normal by retinyl acetate supplementation; treatment with retinoic acid led to an appreciable increase in poly(A) in the mucosa, but considerably less increase in poly(A) in the testes. 4. The incorporation of H332PO4 into the rRNA and tRNA of the testes was lowered by vitamin A deficiency, but no such effects was observed in the liver RNA.

Animals↗

PubMed1977

[Quantitative characteristics of the immunocompetent cells of the large-intestinal mucosa in acute dysentery].

Histological and immuno-morphological examinations of the large intestine mucosa obtained by aspirational biopsy from 38 adult patients with acute dysentery in the mild, moderately severe and severe forms and from 4 normal subjects were carried out. In each case, a per cent ratio of immunocompetent cells in deep and superficial parts of the mucous membrane proper, the content of interepithelial lymphocytes, the cell density of infiltrate per 1 mm2 of the mucous membrane, the number of cells producing IgA, IgM, and IgG per 1 mm2 of the mucous membrane were determined. As the severity of clinical and morphological manifestations of dysentery increased, the number of cells actively producing immunoglobulins was found to increase and epithelium infiltration with lymphocyte to be enhanced. The main role in the development of local immune response in dysentery is played by IgA-producing cells, and in the moderately severe and severe forms of dysentery the number of IgM-producing cells increases.

Adult↗

PubMed1981

Subcellular localization and properties of N-acetylglutamate synthase in rat small intestinal mucosa.

N-Acetylglutamate synthase [EC 2.3.1], which catalyzes the synthesis of N-acetylglutamate, a key effector of carbamoyl-phosphate synthase (ammonia) [EC 6.3.4.16] in the liver of ureotelic animals, was demonstrated to be present in rat small intestinal mucosa. The activity of the enzyme was estimated to be 0.17 nmol N-acetylglutamate formed X (g mucosa)-1 X min-1 at 25 degrees C. Little activity was found in the muscle layer and serosa of the small intestine. The intestinal villous cells were separated from everted intestine, disrupted by nitrogen cavitation, and fractionated into nuclear, mitochondrial, microsomal, and soluble fractions. The mitochondria isolated by this method retained integrity of respiratory function. The mitochondrial fraction was further subjected to isopycnic centrifugation using Percoll (colloidal silica coated with polyvinylpyrrolidone). The activities of N-acetylglutamate synthase and the first two urea cycle enzymes, carbamoylphosphate synthase (ammonia) and ornithine carbamoyltransferase [EC 2.1.3.3], were cofractionated with mitochondrial marker enzymes during the cell fractionation and the isopycnic centrifugation. N-Acetylglutamate synthase, purified 8-fold from the acetone powder extract of small intestinal mucosa, had a high substrate specificity for L-glutamate and acetyl-CoA. The synthase reaction fitted normal Michaelis-Menten kinetics with respect to both L-glutamate (apparent Km, 2.5 mM) and acetyl-CoA (apparent Km, 0.8 mM). L-Arginine stimulated the enzyme activity by increasing the maximal velocity with no effect on apparent Km values for the substrates. These properties were similar to those of the rat liver enzyme (Shigesada & Tatibana (1978) Eur. J. Biochem. 84, 285-291). These results suggest that a function of the intestinal N-acetylglutamate is to activate carbamoyl-phosphate synthase (ammonia) and to allow citrulline synthesis in the tissue.

Acetyltransferases↗

PubMed1994

Biosynthesis of 9-cis-retinoic acid from 9-cis-beta-carotene in human intestinal mucosa in vitro.

The role of 9-cis-beta-carotene (9-cis-beta-C) as a potential precursor of 9-cis-retinoic acid (9-cis-RA) has been examined in human intestinal mucosa in vitro. By using HPLC, uv spectra, and chemical derivatization analysis, both 9-cis-RA and all-trans-retinoic acid (all-trans-RA) have been identified in the postnuclear fraction of human intestinal mucosa after incubation with 9-cis-beta-C at 37 degrees C. The biosynthesis of both 9-cis-RA and all-trans-RA from 9-cis-beta-C was linear with increasing concentrations of 9-cis-beta-C (2-30 microM) and was linear with respect to tissue protein concentration up to 0.75 mg/ml. Retinoic acid was not detected when a boiled incubation mixture was incubated in the presence of 9-cis-beta-C. The rate of synthesis of 9-cis- and all-trans-RA from 4 microM 9-cis-beta-C were 16 +/- 1 and 18 +/- 2 pmol/hr/mg of protein, respectively. However, when 2 microM all-trans-beta-C was added to the 4 microM 9-cis-beta-C, the rate of all-trans-RA synthesis was increased to 38 +/- 6 pmol/hr/mg of protein, whereas the rate of 9-cis-RA synthesis remained the same. These results suggest that 9-cis-RA is produced directly from 9-cis-beta-C. Furthermore, incubations of either 0.1 microM 9-cis- or all-trans-retinal under the same incubation conditions showed that 9-cis-RA could also arise through oxidative conversion of 9-cis-retinal. Although only 9-cis-RA was detected when 9-cis-RA was used as the substrate, the isomerization of the all-trans-RA to 9-cis-RA cannot be ruled out, since both all-trans-RA and trace amounts of 9-cis-RA were detected when all-trans-retinal was incubated as the substrate. These data indicate that 9-cis-beta-C can be a source of 9-cis-RA in the human. This conversion may have a significance in the anticarcinogenic action of beta-C.

Carotenoids↗

PubMed1997

Postnatal development of lymphocyte subpopulations in the intestinal mucosa in goat.

The incidence and location of CD2+, CD4+, CD8+ and gamma/delta T-lymphocytes and B-lymphocytes were studied in the intestinal mucosa in goats of one week, one month, three months and seven months old, using monoclonal antibodies and immunohistochemical methods. At all ages CD2+ lymphocytes were the major subpopulation in the intestinal mucosa, more numerous in the small than in the large intestine and in the villi than in the crypt region. In one week-old animals most of CD2+ lymphocytes were scattered in the lamina propria and the number of lymphocytes that expressed CD4 was less than those that expressed CD8, resulting in a CD4/CD8 ratio less than 1. CD2+ lymphocytes increased markedly until one month old, with a higher increase of CD4+ subpopulation than CD8+ with an inversion of the CD4/CD8 ratio. CD4+ lymphocytes were localised in the lamina propria forming clusters, whereas CD8+ lymphocytes were scattered peripherally under the epithelium and in older animals from three month old, CD8+ lymphocytes were also abundant between epithelial cells. The gamma/delta T-lymphocytes recognised with the mAb CACTB6A represented a minor subpopulation located between epithelial cells or in the lamina propria, no evident changes were observed with age. IgM+ cells were a minor subpopulation in all animals (never higher than 1 cell per 1500 microns-2) located in the crypt region of the lamina propria.

Aging↗

PubMed1983

Decreased incorporation of 14C-glucosamine relative to 3H-N-acetyl glucosamine in the intestinal mucosa of patients with inflammatory bowel disease.

The synthesis of glycoproteins was investigated in intestinal mucosa from patients with inflammatory bowel disease (IBD) and from those with various other conditions. The incorporation into acid-insoluble macromolecules of the amino sugar glucosamine, the first and committed metabolite in the biosynthetic sequence, and its immediate derivative, N-acetyl glucosamine was determined. Tissue was incubated with 1-2 nmol 14C-glucosamine and 3H-N-acetyl glucosamine and the simultaneous incorporation of both isotopes was measured. Bowel tissue from areas microscopically uninvolved in active disease process was examined. Values for the incorporation of both substrates into acid-soluble constituents were similar for both IBD and non-IBD groups, as was also the incorporation of 3H into acid-insoluble constituents. The incorporation of 14C, however, when expressed relative to that of 3H in each individual patient, i.e., 14C/3H, was distinctly different in IBD cases. In 26 non-IBD samples this ratio ranged from 0.04-0.26 with a mean of 0.097 +/- 0.009. In nine cases of Crohn's disease values ranged from 0.013-0.06 with a mean of 0.039 +/- 0.011 (p less than 0.01); in nine cases of ulcerative colitis values were 0.007-0.06 with a mean of 0.031 +/- 0.006 (p less than 0.01). It is concluded that the step involving the N-acetylation of the amino sugar is relatively deficient in patients with IBD and this could reduce the synthesis of the glycoprotein cover which protects the mucosa from damage by bowel contents.

Acetylglucosamine↗

PubMed1982

Glutathione S-transferase activity in liver, lung and intestinal mucosa of aging female mice.

1. Changes in the activity of glutathione S-transferase (GST) in liver, lungs and intestinal mucosa of female Swiss-Webster mice with age were determined. 2. GST activity increased with age from 1 to 9 months, reached a maximum activity at 9 months and decreased thereafter with advanced age in all three tissues. 3. GST activity decreased by approximately 75% in liver between 9 and 18 months, with decreases of 65 and 64% occurring over the same time period for lung and intestinal mucosa, respectively.

Aging↗

PubMed1982

The TCDD receptor in rat intestinal mucosa and its possible dietary ligands.

Induction of aryl hydrocarbon hydroxylase (AHH) by polycyclic aromatic hydrocarbons and other inducers such as 2,3,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to occur following binding of the inducer to a soluble receptor protein similar to steroid hormone receptors. This receptor is usually called the TCDD receptor, since TCDD has the highest affinity of all known ligands for the receptor. In the present paper a receptor for TCDD in cytosol from rat intestinal mucosa has been studied, using isoelectric focusing in polyacrylamide gel. This receptor's biochemical properties were found to be similar to those of the TCDD-receptor in rat liver cytosol. The dissociation constant (Kd) of the 3H-TCDD-receptor complex in rat intestinal mucosa was 0.7-3.1 nM, and it was present at a concentration of 70-80 fmol/mg protein. Starvation did not significantly increase the receptor level. The affinities of some potential dietary ligands for the TCDD receptor in rat intestinal mucosa were also studied. Indole-3-carbinol had 1/2,600 of the affinity of TCDD for the receptor protein. Butylated hydroxyanisole (BHA), transstilbene oxide and quercetinpentamethylether competed even more weakly with 3H-TCDD for binding to the receptor. The biological significance of the occurrence of low-affinity ligands of dietary origin for the TCDD receptor is uncertain at the present time.

Animals↗

PubMed2003

[Expression of interleukin 18 in intestinal mucosa of patients with inflammatory bowel disease and its implications].

OBJECTIVE: To investigate the expression of interleukin 18 (IL-18) in intestinal mucosa of patients with inflammatory bowel disease (IBD) and its relation with disease active state. METHODS: IL-18mRNA transcripts were evaluated by using a semiquantitative RT-PCR protocol. Specimens of 23 Crohn's disease (CD) and 20 ulcerative colitis (UC) patients and 20 controls were studied by immunohistochemical staining. RESULTS: Transcripts of IL-18 were found to be increased significantly in intestinal mucosa from active CD compared with UC and control. Immunohistochemical staining analysis localized the expression of IL-18 to intestinal epithelial cells and lamina propria (macrophages and dendritic cells, mainly). Staining was more intense in active CD compared with UC and control. Both transcriptions and staining of IL-18 in active UC were elevated, but there was no significant difference compared with control. Expression of IL-18 decreased in inactive CD (n = 9) or UC (n = 11) compared with active state of the same patients, and the difference in CD had significance. CONCLUSION: IL-18 may be involved in the pathogenesis of IBD and related with CD activity.

Colitis, Ulcerative↗