Duodenal Cells Research Articles

O-254 - actions of motilin on the stomach and duodenal smooth muscle cells of the rabbit.

O-254 - actions of motilin on the stomach and duodenal smooth muscle cells of the rabbit.

Immuno‐electron microscopic localization of estradiol receptor in cells of male and female reproductive and non‐reproductive organs

The localization of estradiol receptor (ER) in various tissues and their distribution in sub-cellular compartments were studied by means of immunogold-electron microscopic methods using a site-directed polyclonal antibody developed against a peptide from the DNA binding site of ER. This method was used to determine the presence and localization of ER in tissues and cells of male and female reproductive and non-reproductive organs. In the female reproductive tract, endometrial cells and the cells of the corpus luteum were found to contain ER. In non-reproductive organs of both sexes the following cell types showed significant labeling: hepatocytes, epithelial duodenal cells, striated muscle fibers, cells of the proximal convoluted tubules of the kidney, lymphocytes, neurons, and adipose cells. Alveolar epithelial cells were studied only in female specimens and were labeled by the anti-ER. Prostatic and epididymal epithelial cells were found to be labeled in the male reproductive organs. In all these cells a higher density of label was found in the nucleus, especially in the space between the clumps of compact chromatin, as was previously found in epithelial endometrial cells. These results suggest that estradiol exerts its effects through a common nuclear mechanism in cells of male and female reproductive and non-reproductive organs.

Adherence of Helicobacter pylori to primary human gastrointestinal cells.

Helicobacter pylori adheres only to gastric cells in vivo. However, the organism adheres to a wide variety of nongastric cells in vitro. In this study, we have used flow cytometry to assess the adherence of H. pylori to primary epithelial cells isolated from gastric, duodenal, and colonic biopsy specimens by collagenase digestion. After incubation of bacteria and cells together and subsequent staining with a two-stage fluorescein isothiocyanate-labelled H. pylori antibody method, cells with adherent bacteria could be easily distinguished from cells without bacteria. Binding to Kato III cells (a gastric adenocarcinoma cell line) was saturable when bacteria and cells were mixed at a ratio of 250:1. Adherence to cells isolated from gastric biopsy specimens was significantly better than adherence to cells isolated from duodenal or colonic biopsy specimens. Almost 70% of gastric cells had bacteria bound, in contrast to 30% of duodenal cells and 32% of colonic cells (P < 0.0001). There was no correlation between expression of hemagglutinins by the bacteria and ability to bind to either Kato III cells or primary epithelial cells isolated from gastric biopsy specimens. In view of the strict tropism that the organism exhibits in vivo for gastric cells, the results of this study indicate that primary cells are ideal for assessing the factors that might play a role in the pathogenesis of disease caused by the organism.

B‐Cell Activation in Duodenal Mucosa after Oral Cholera Vaccination in IgA Deficient Subjects with or without IgG Subclass Deficiency

Alterations in duodenal Ig-producing cells induced by two oral cholera vaccinations were studied by two-colour immunofluorescence in mucosal tissue sections from adults with selective IgA deficiency (IgAD), either with (n = 7) or without (n = 9) frequent infections, infection-prone patients with combined IgAD and IgG subclass deficiency (IgGSD) (n = 7), and normal control subjects (n = 11). The proportion of IgG-producing cells prior to immunization tended to be lower in the symptomatic IgAD subjects than in the clinically healthy ones. In the first subgroup the absolute number of IgG cells per intestinal length unit was significantly increased after immunization (P < 0.04), and this tendency was also observed in the healthy IgAD subjects (6/9) and in those with combined deficiency (5/7). Very few IgAD subjects responded with an increase of IgM-producing cells. The normal controls responded variably in all major immunocyte classes, in the order IgA > IgG > IgM. Compared with these controls, the patients with combined IgAD and IgGSD showed significantly increased IgG1 (P < 0.01) and reduced IgG2 (P < 0.006) proportions, which was in accordance with their serum subclass levels. Our study showed that oral cholera vaccination preferentially activates intestinal IgG-producing cells in IgAD subjects. This result agreed with data recently obtained by ELISPOT in the same patients with regard to antibody-forming cells specific for cholera toxin. Both methods suggested that IgG rather than IgM antibodies are elicited as compensation for a lacking IgA response. However, our overall results showed that intestinal B-cell activation is quite variable after oral cholera vaccination. Although such vaccination might be of importance for enhancing mucosal immunity also in IgAD patients, a concurrent gut disease could possibly be aggravated by IgG-mediated mucosal immunopathology in the absence of anti-inflammatory IgA antibodies.

Purification and immunohistochemical tissue localization of human xanthine oxidase

Xanthine oxidase was purified 1600-fold from human liver cytosol. The purified enzyme was shown as a single band of 300 kDa on polyacrylamide gel electrophoresis and 150 kDa on SDS-PAGE. Using this purified enzyme, polyclonal antibody against xanthine oxidase was raised in a rabbit. On Ouchterlony's double immunodiffusion method, the raised antibody and the human liver cytosol made a precipitation line stained by activity stain and protein stain, respectively. With the raised anti-xanthine oxidase sera, the immunohistochemical localization of xanthine oxidase in human tissues was examined. Immunostaining of frozen hepatic tissue section showed that the cytoplasm of hepatocytes and endothelial lining cells were stained. In a number of other tissues, the xanthine oxidase antigen was detected only in the endothelial lining cells from heart, kidney, brain, aorta, lung and mesentery, except for the duodenal mucosa cells. A possible role for xanthine oxidase in the endothelial cells from various human tissues in the pathogenesis of reperfusion injury was suggested.

Vasopressin and vasopressin-associated neurophysin are present in gastric and duodenal cells of Brattleboro and Long-Evans rats.

Vasopressin and vasopressin-associated neurophysin are present in gastric and duodenal cells of Brattleboro and Long-Evans rats.

Characterization of dietary phosphorus-dependent duodenal calcium uptake in vitamin D-deficient chicks.

The effect of dietary phosphorus on intestinal calcium uptake was examined in duodenal cells isolated from vitamin D-deficient chicks. Cells from chicks on a high phosphorus diet accumulated calcium at a rate 38% higher than cells from animals on a normal phosphorus diet. Diet high in calcium did not affect calcium absorption in duodenal cells. The dietary phosphorus effect on calcium absorption was specific. Uptake of alpha-methyl glucose was not altered. Increase in calcium absorption by a high phosphorus diet was not due to a change in cellular energy metabolism nor to the content of phosphorus in cells. Kinetically, a high phosphorus diet increased the Vmax of calcium uptake; the affinity for calcium was unaffected. The effectiveness of dietary phosphorus to enhance the intestinal calcium uptake could also be demonstrated in brush border membrane vesicles. The increase in calcium uptake was not due to an alteration in membrane binding capacity nor to calcium efflux from vesicles. To test the hypothesis that a high phosphorus diet may affect membrane transport by altering phospholipid metabolism in duodenal cells, we examined the phospholipid content in isolated brush border membranes. The content of phosphatidylcholine, phosphatidylserine, phosphatidylinositol and phosphatidylethanolamine was not altered by the high phosphorus diet. These findings suggest that the vitamin D-independent and dietary phosphorus-dependent effect on intestinal calcium absorption was primarily due to a change in the calcium flux at the luminal side of the cells. However, the precise mechanism is still not clear.

Interleukin-1 modulatory effect on the action of chemotherapeutic drugs and localized irradiation of the lip, duodenum, and tumor

Purpose: This study was conducted to examine the radioprotective and radiochemoprotective capabilities of interleukin 1β (IL-1) on two acute-reacting normal tissues of the C3H mouse, the mucosa of the lip and the duodenum. Also assessed was the modulating effect of IL-1 on tumor growth in the same strain of mice. Methods and Materials: IL-1 was administered to C3H/Km mice in combination with fractionated irradiation, or with cyclophosphamide, cisplatin, or 5-fluorouracil (5FU) followed by irradiation. Normal tissue damage was evaluated in the mouse lip, using a subjective scoring system for tissue reaction, and in the duodenum, using the crypt cell survival assay. RIF-1 fibrosarcoma tumor response was assayed with the regrowth delay method. Results: IL-1 protected against the acute reaction produced by fractionated irradiation in the lip mucosa, shifting the dose-response curve by 3.8 Gy. IL-1 was protective when injected intraperitoneally 24 hr before CY or c-DDP, which were given immediately before the first of five daily radiation dose fractions. The dose-response curves for cyclophosphamide and cisplatin were shifted 4.0 Gy and 1.6 Gy, respectively. IL-1 did not protect against 5FU toxicity when treatments were administered in that same sequence; however, when 5FU was given 4 or 8 hr before IL-1 and the first radiation dose fraction followed 20 or 16 hr later, there was significant protection and the curves were separated by 1.5 Gy or 3.5 Gy. IL-1 also protected duodenal crypt cells against the cytocidal effect of fractionated irradiation, with a dose difference of 1.5 Gy and an improvement of crypt survival of 11.7%. It was even more protective for these cells against the enhanced drug toxicity when cyclophosphamide or 5FU were administered immediately before the first of five daily radiation doses, with the dose differences of 4.4 and 5.3 Gy, respectively, and improvements of crypt survival of 33.8 and 29.9%, respectively. There was no modification by IL-1 of the effect of irradiation alone on the RIF-1 tumor. Conclusion: This study demonstrates the potential for use of IL-1 as an auxiliary in combinations with chemotherapeutic agents and radiation. It also indicates that for some drugs, such as 5FU, IL-1 effects may be sequence dependent.

Pathogenesis of genetic haemochromatosis.

Genetic haemochromatosis is an autosomal recessive inherited iron overload disease. The genetic defect and the underlying metabolic error are not known. Several observations indicate that the 2-4-fold increase of iron absorption is due to a regulatory defect of a membrane iron transport system in duodenal mucosal cells. The key pathophysiologic factor may be the increase of gut-derived non-transferrin bound iron liganded to low-molecular mass organic molecules. A putative membrane carrier protein for non-transferrin bound iron was identified and preliminary data suggest its enrichment in plasma membranes of human mucosal cells as well as in liver and other organs which are affected in genetic haemochromatosis. Cellular accumulation of ionic iron leads to peroxidative decomposition of organelle membrane phospholipids with the consequence of cell degeneration and cell death. Impairment of organ function and structural alterations such as cirrhosis of the liver are clinical manifestations.

Diagnosis of food allergy by counting IgE-positive duodenal cells

Le dénombrement des cellules contenant des immunoglobulines a été effectué par immunofluorescence au sein des muqueuses gastrique, duodénale et jéjunale chez 120 sujets sains et 200 malades chez lesquels une sensibilisation alimentaire avait été mise en évidence par la détection des IgE spécifiques plasmatiques et la réactivité intestinale par une épreuve de provocation orale. Aucun sujet sain et aucun malade n'était porteur de parasite. Les nombres de cellules contenant de l'IgA, de l'IgM, de l'IgG ou de l'IgD étaient semblables chez les malades et chez les témoins. Chez les allergiques les cellules renfermant de l'IgE présentes dans la lamina propria de l'intestin étaient systématiquement en nombre très accru. Ceci a été observé en ce qui concerne la muqueuse gastrique chez seulement 118 des 200 malades. Cinquante autres malades suspectés de présenter une allergie alimentaire et présentant un accroissement de la densité des cellules duodénales contenant de l'IgE ont été traités par le cromoglycate disodique oral pendant un minimum de trois mois. Trente-trois malades ont observé une guérison ou une amélioration marquée de leurs symptômes. Le dénombrement des cellules duodénales contenant de l'IgE, mais non celui des cellules de l'estomac, représente un moyen efficace de diagnostiquer une allergie alimentaire chez des sujets exempts de parasites intestinaux. The quantitative distribution of immunoglobulin-containing cells in the gastric, duodenal and jejunal mucosae of 120 healthy controls and of 200 food-allergic patients, in which sensitization had been demonstrated by the detection of IgE plasma antibodies and intestinal reactivity by oral provocation test, has been studied after immunofluorescence staining. No patient or control subject was bearing gut parasites. The numbers of IgA-, IgM-, IgG- and IgD- containing cells were similar in patients and in controls. In food-allergic patients, the numbers of IgE-positive cells in the lamina propria was markedly increased in all small intestinal biopsy specimens studied. This was observed only in 118 out of 200 gastric biopsy specimens. Fifty other patients suspected of food allergy and presenting an increased number of duodenal IgE-positive cells were treated with oral sodium cromoglycate for a minimum of three months. Thirty-three patients reported healing or marked improvement. Enumerating IgE-positive cells from the duodenum, but not from the stomach, may be an efficient method for the diagnosis of food allergy in patients without gut parasites.

Bicarbonate transport by rabbit duodenum in vitro: Effect of vasoactive intestinal polypeptide, prostaglandin E2, and cyclic adenosine monophosphate

Background: Duodenal surface cells secrete bicarbonate that provides a barrier against injury. The current experiments were performed to identify duodenal bicarbonate regulatory and transport pathways. Methods: Rabbit proximal duodenal mucosa were mounted in chambers under short-circuited conditions. Bicarbonate transport, short-circuit current (Isc), and potential difference (PD) were quantitated in response to prostaglandin E2 (PGE2), vasoactive intestinal polypeptide (VIP), and dibutyryl cyclic adenosine monophosphate (db-cAMP). Anoxia (N2), 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS) and Cl−free solutions, ouabain, and Na-free solutions were also studied, as was the effect of VIP and PGE2 on duodenocyte cAMP. Results: PGE2, VIP, db-cAMP, and theophylline significantly increased bicarbonate secretion, Isc, and PD. Ouabain, Na+-free bathing solutions, and anoxia (N2) inhibited the responses. DIDS and Cl− -free solutions abolished the PGE2-induced response, reduced the response to VIP by about 50%, and had no effect on the response to db-cAMP. After PGE2 and VIP, cAMP concentration increased, yet was likely independent of bicarbonate secretion. Conclusions: Mammalian duodenal HCO3− transport requires Na+, Na+/K+-adenosine triphospatase and O2-dependent metabolic pathways and is stimulated by PGE2, VIP, and cAMP, acting by distinct pathways.

Function of Integrin in Duodenal Mucosal Uptake of Iron

AbstractA mechanism for the absorption of inorganic iron in the small intestine is described in which integrins appear to play an important role in the passage of iron across microvillous membranes. Biochemical isolates from microvillous preparations of duodenum from rats dosed with radioiron showed radioactivity concentrated in integrins. The presence of integrins on mucosal surfaces of duodenal cells was confirmed by immunofluorescent microscopy using anti-integrin monoclonal antibodies. Immunoprecipitation methods were used to show that microvillous radioiron was precipitated with anti-integrin antibodies and that mobilferrin, a 56-Kd cytosol iron-binding protein, coprecipitated with integrins. We postulate from these data that the mucosal uptake of iron from the gut lumen is mediated via an integrin-mobilferrin pathway.

Function of integrin in duodenal mucosal uptake of iron

A mechanism for the absorption of inorganic iron in the small intestine is described in which integrins appear to play an important role in the passage of iron across microvillous membranes. Biochemical isolates from microvillous preparations of duodenum from rats dosed with radioiron showed radioactivity concentrated in integrins. The presence of integrins on mucosal surfaces of duodenal cells was confirmed by immunofluorescent microscopy using anti-integrin monoclonal antibodies. Immunoprecipitation methods were used to show that microvillous radioiron was precipitated with anti-integrin antibodies and that mobilferrin, a 56-Kd cytosol iron-binding protein, coprecipitated with integrins. We postulate from these data that the mucosal uptake of iron from the gut lumen is mediated via an integrin-mobilferrin pathway.

Intranuclear Inclusions of Unknown Pathogenic Significance from Diagnostic Cases in Three Avian Species

Intranuclear inclusions were observed with light microscopy in tissues from necropsy cases from three different species of birds. Because of the nature of these inclusions, the species affected, or their distribution, the inclusions were considered of unknown pathogenic significance. The inclusions were examined ultrastructurally. Parvovirus-like particles were observed in the intranuclear inclusions of pigeon hepatocytes and duodenal stromal cells from a quail. Finely granular eosinophilic intranuclear inclusion bodies from two unrelated pigeon cases were found to be composed of loosely organized filaments. One liver sample from a 16-week-old laying chicken had prominent eosinophilic hepatocellular intranuclear inclusions composed of electron-dense coarsely granular amorphous material.

BK1 and BK2 bradykinin receptors in the rat duodenum smooth muscle.

1. The dual action of bradykinin (relaxation and contraction) on the rat duodenum was investigated by studying its effect on adenosine 3':5'-cyclic monophosphate (cyclic AMP) levels in cultured duodenal smooth muscle cells, and the effects of apamin on the isolated muscle responses to agonists and antagonists of BK1 and BK2 receptors. 2. No change was observed in the cyclic AMP content of cultured cells incubated with up to 100 nM bradykinin. 3. Apamin (100-500 nM) inhibited the relaxant component and enhanced the contractile component of the responses to bradykinin and to the BK2-specific analogue [Thi5,8,D-Phe7]-bradykinin. 4. Apamin (100-500 nM) did not affect the contractile response of stretched duodenum preparation to the BK1-specific agonist des-Arg9-bradykinin. 5. The BK2 antagonist, [D-Arg0Hyp3Thi5,8,D-Phe7]-bradykinin, at a concentration which completely inhibited the relaxant response to bradykinin and to [Thi5,8,D-Phe7]-bradykinin, also prevented the contraction in response to either agonist in the presence of apamin. 6. Our results demonstrate two populations of bradykinin receptors in rat duodenum: a BK2 subtype responsible for the biphasic response of the non-stretched duodenum, and a BK1 subtype responsible for the contractile effect on the stretched tissue.

Ontogeny of calbindin-D28K and calbindin-D9K in the mouse kidney, duodenum, cerebellum and placenta.

The appearance of the calcium-binding proteins (CaBP-D28K and CaBP-D9K) in embryonic mice tissues was determined using a sensitive immunohistochemical assay. CaBP-D28K first appears in myenteric nerve plexuses of the duodenum on day E15, in duodenal villus cells on day E16, in Purkinje cells of the cerebellum on day E19, in cells of the mesonephric duct on day E11 and in the metanephric duct on day E12. CaBP-D9K first appears in enterocytes of the duodenum on day E18, in trophoblastic giant cells (TGC) of the placenta on day E10, and in the metanephric duct on day E15. A differential time of appearance and colocalization of the two CaBPs is demonstrated in the embryonic mouse kidney, suggesting either that vitamin D does not control both CaBPs in the foetus or that the vitamin D control is unequal. The early appearance and location of CaBP-D9K in TGCs may suggest that these cells play an important role in transplacental transfer of calcium.

Iron-transferrin binding to isolated guinea pig enterocytes and the regional localisation of intestinal iron transfer during ontogeny

Neonatal animals are iron replete but in comparison with adults they display increased intestinal iron absorption. In order to examine possible mechanisms for this developmental adaptation we have measured the appearance of iron in peripheral blood following 30 min exposure of duodenal and ileal segments of adult and neonatal guinea pigs in vivo to 59Fe-ascorbate. Parallel experiments have determined the kinetics of 125I-labelled diferric transferring binding to villus enterocytes isolated from duodenum and ileum. In adult animals the rate of appearance of 59Fe in peripheral blood was 11-fold greater following duodenal, compared to ileal exposure to the radioligand. No such regional difference was detected in the neonate. Isolated cells showed saturable binding of [ 125I]transferrin which was maximal between 30 and 60 min. The kinetics of specific transferrin binding by adult duodenal and ileal enterocytes were similar and were also not significantly different to respective values in neonatal duodenal and ileal cells. Thus, it is likely that increased iron absorption in the neonate is due in part to enhanced ileal iron transfer. The interaction of transferrin with its receptor, however, is not involved in this developmental change in uptake.

Visualization of DNA within mitochondria by osmium-ammine staining of mouse duodenal crypt cells.

Previous investigators have examined mitochondrial DNA (mtDNA) in the electron microscope (EM) after extraction from mitochondria and rotary shadowing. We have observed mtDNA in situ by the osmiumammine procedure for specific staining of DNA in the EM. The procedure was modified to improve the regularity of the staining and then applied to the rapidly dividing cells present in mouse duodenal crypts. In the stained sections of these cells, 25% of the mitochondria exhibited discrete reactive filaments. The filaments, whether observed directly or in stereopairs, appeared either irregular or arranged into distinct patterns, some of which were similar to those previously described after rotary shadowing of duplicating mtDNA: namely, simple and double circular figures, displacement loops and supercoiled forms. The filaments could be traced in serial sections of the same mitochondria and, therefore, were not artifacts. Moreover, their disappearance after DNase digestion demonstrated that they were composed of DNA. It is concluded that mtDNA can be visualized by the modified osmium-ammine technique and may show patterns that can be interpreted as phases in its replication.

Short term effects of animal venoms on the mitotic index of the duodenal mucosa of albino rats.

Short term administration of the venoms of the snakes Naja haje, Naja nigricollis, and Cerastes vipera and of the scorpion Leiurus quinquestriatus on the mitotic index of the duodenal mucosal cells of the white rat, Rattus rattus, has been studied. All the venoms increased the number of dividing cells of the duodenal mucosa significantly. Naja haje crude venom was fractionated into three fractions. Fraction I had no effect on the mitotic index whereas fractions II and III increased it significantly. Treatment of rats with Naja haje venom fractions II and III after blocking the histamine or the serotonin receptors did not affect the stimulatory action of the two venom fractions on the mitotic index, which it increased significantly. It was suggested that the venoms of Naja haje, Naja nigricollis, Cerastes vipera, and Leiurus quinquestriatus and Naja haje venom fractions possessed a mitogenic activity. Fraction II of Naja haje venom acted through both the muscarinic and adrenergic receptors while fraction III acted on the adrenergic ones.

Abnormal intestinal regulation of calbindin-D9K and calmodulin by dietary calcium in genetic hypertension

Using isolated duodenal cells from spontaneously hypertensive rats (SHR) and their normotensive controls, Wistar-Kyoto rats (WKY), we previously showed that cellular calcium flux was decreased in SHR and that increasing dietary calcium (from 1 to 2%) eliminated strain differences in Ca2+ fluxes. The present study was carried out to investigate the role of calbindin-D9K and calmodulin in the flux difference and dietary calcium effects. Calbindin-D9K and calmodulin were separated by sodium dodecyl sulfate (SDS) gel electrophoresis in duodenal protein extracts of SHR and WKY (12-14 and 24-26 wk old) fed either a 1 or 2% calcium diet and measured by a ligand blotting (45Ca) technique. Young SHR had a significantly lower calbindin-D9K (P less than 0.001) than did WKY on either diet. Calmodulin was significantly lower in young SHR than in WKY (P less than 0.002). There was no strain difference in calmodulin in older rats fed the normal calcium diet. Calbindin-D9K was significantly decreased by the high-calcium diet in both strains at both ages. There was a significant correlation between duodenal calbindin-D9K and plasma levels of calcitriol (r = +0.80, P less than 0.001) in WKY but not in SHR. Calmodulin was significantly decreased by dietary calcium in mature WKY (4.8 +/- 0.2 vs. 3.7 +/- 0.4 micrograms/mg cell protein, P less than 0.03), demonstrating a potential regulation by dietary calcium of this protein. Finally, there was a significant correlation between calbindin-D9K and calmodulin (r = 0.59, P less than 0.001) in WKY but not in SHR.(ABSTRACT TRUNCATED AT 250 WORDS)