Hamster Intestine Research Articles

Proximal-distal gradient of sulfate transport by brush border membrane vesicles from hamster small intestine

Inorganic sulfate uptake by brush border membrane vesicles prepared from proximal and distal small intestine of hamster was studied. Vesicles were prepared by calcium precipitation and uptake was measured by rapid filtration. In the presence of an inwardly directed sodium gradient, vesicles from both proximal and distal segments demonstrated typical “overshoots” of sulfate concentration characteristic of sulfate-sodium co-transport. Sulfate uptake comprised non-saturable and saturable components. Non-saturable uptake, i.e. uptake in the absence of a sodium gradient, was greater in vesicles from distal (126) than proximal (89) intestine (data are pmoles/mg protein per 30 sec at 1 mM). V max for sodium-dependent uptake was the same in vesicles from both proximal and distal segments. However, uptake rate was greater in the vesicles from the distal than the proximal segment over the concentration range 0.05–5 mM, because K t (mM) for vesicles from the distal segment (0.8) was one-third that for vesicles from the proximal segment (2.2). Prior studies with full thickness intestinal segments of hamster show the same proximal-distal gradient we found with vesicles. We conclude that at physiologic concentrations 1) the proximal-distal gradient in sulfate transport is determined at least in part by brush border membrane function; 2) intestinal sulfate uptake is by sulfate-sodium co-transport and its rate is determined by carrier affinity not carrier density.

Primary culture of the enteric nervous system from neonatal hamster intestine: Selection of vasoactive intestinal polypeptide-containing neurons

The enteric nervous system is a major division of the autonomic nervous system and is responsible for the regulation of gastrointestinal function. The objective of the present study was to develop a simple and effective technique for isolating and culturing neurons of the enteric nervous system that would permit characterization of their development and regulatory peptide content. This was accomplished using a dispersed intestinal cell preparation cultured under conditions designed to support the growth and differentiation of neurons and neuroendocrine cells. Newborn hamster intestine was digested in 0.1% collagenase, mechanically dispersed, and cultured in RPMI 1640 supplemented with 2.5% serum and other additives. Phase and bright-field microscopy demonstrated neuronal cells and fibers after the second day in culture. This was confirmed by immunohistochemistry using antibodies directed against neurofilament and vasoactive intestinal polypeptide. Acetic acid extracts of the culture indicated that during the first 4 days of the culture the content of vasoactive intestinal polypeptide increased, whereas the content of substance P, mammalian bombesin, and neurotensin declined. High-performance liquid chromatography and fast protein liquid chromatography confirmed that the immunoreactive vasoactive intestinal polypeptide coeluted with synthetic and iodinated forms of the peptide. This study describes a technique for primary culture of intestinal tissue that supports the survival of enteric neurons and permits analysis of the development and synthetic and secretory characteristics of the enteric nervous system.

Adaptation of intestinal enzymes to seasonal and dietary changes in a hibernator: the European hamster (Cricetus cricetus).

Effects of diet, hibernation and seasonal variations on hydrolase activities were determined in mucosa and purified brush border membranes of the small intestine of European hamsters. Wild hamsters captured in April and fed for several weeks with an equilibrated laboratory chow (20% protein, 50% carbohydrates) exhibited a rise in disaccharidase activities (sucrase, isomaltase, lactase) but no changes in aminopeptidase N activity. During deep hibernation, in contrast to sucrase and isomaltase activities which showed only minor changes, lactase activity was significantly enhanced along the jejunoileum, and aminopeptidase N activity was maximum in the ileum. After a short period (48 h) of wakefulness and feeding following 10 days of starvation during the hibernation period, the activities of the disaccharidases and of aminopeptidase N returned to values measured in active animals. In contrast to the nutritional state, which has an important impact on the activities of intestinal enzymes, season has little effect on the intestine of the active animal under a controlled environment. The pattern of enzyme activities which occurs along the small intestine in the hibernating animal may be a prerequisite for optimum digestion during the short phases of waking during the hibernation period of the European hamster.

Status of the microsomal mixed function oxidase system in the intestine, lungs and kidneys of hamsters during infection with Ancylostoma ceylanicum

Tekwani B. L., Tripathi L. M., Mukerjee S., Visen P. K. S., Katiyar J. C., Shukla O. P. and Ghatak S. 1988. Status of the microsomal mixed function oxidase system in the intestine, lungs and kidneys of hamsters during infection with Ancylostoma ceylanicum. International Journal for Parasitology 18: 11–14. Infection of golden hamsters with Ancylostoma ceylanicum causes significant alterations in microsomal cytochrome P-450 and associated components in intestine, lungs and kidneys. In intestinal microsomes, cytochrome P-450, cytochrome b 5, heme, cytochrome b 5 reductase, NADPH-cytochrome c reductase and benzo(a)pyrene hydroxylase decreased considerably. This generalized damage in jejunal microsomes appears to be due to marked pathological lesions in this tissue. Lung microsomes exhibited a decrease in cytochrome P-450, heme and benzo(a)pyrene hydroxylase, while cytochrome b 5, and cytochrome b 5 reductase were not significantly affected. Renal microsomes showed elevation in cytochrome P-450 and benzo(a)pyrene hydroxylase, while other associated components remained unaffected.

Lesions of experimentally induced Tyzzer's disease in Syrian hamsters, guineapigs, mice and rats.

The relative susceptibilities of C57BL/6NCR and BALB/cANNCR mice, F344/NCR rats, 2/NCR guineapigs and CR:RGH Syrian hamsters to Bacillus piliformis infection were determined by orally inoculating 20 weanling females from each species with suspensions of B. piliformis spores. Animals from each group were sequentially necropsied over 2 week periods to document the lesions produced. No significant gross or microscopic lesions were observed in the BALB mice or the Fischer rats. Gross and microscopic lesions were observed in the livers and intestines of many guineapigs and hamsters killed 3-14 days after inoculation. A large lesion was observed in the left cardiac ventricle of one C57BL mouse 10 days after inoculation. Warthin-Starry silver-stained tissue sections revealed clusters of B. piliformis within the cytoplasm of intestinal epithelial cells, smooth muscle cells, hepatocytes and myocytes bordering foci of necrosis in the intestines, liver and heart.

Lactobacillus hamsteri, a new species from the intestine of hamsters.

Lactobacillus hamsteri, a new species from the intestine of hamsters.

Inhibitory effect of chlorogenic acid on methylazoxymethanol acetate-induced carcinogenesis in large intestine and liver of hamsters

The effect of dietary chlorogenic acid on methylazoxymethanol (MAM) acetate-induced carcinogenesis was examined in Syrian golden hamsters. The combined incidence of total large intestinal tumors from male and female hamsters, and the combined incidence of large intestinal adenocarcinomas or the incidence of the carcinomas of male or female animals of the group given a single intravenous injection of MAM acetate (20 mg/kg body wt) and then fed the diet containing 0.025% chlorogenic acid for 24 weeks were significantly lower than those of hamsters given MAM acetate alone. The numbers of hyperplastic liver cell foci in male and female hamsters given MAM acetate and chlorogenic acid were also significantly smaller than those of hamsters given MAM acetate alone. These results indicate an inhibitory effect of chlorogenic acid on MAM acetate-induced carcinogenesis in hamsters.

Identification of Diphyllobothrium dendriticum and Diphyllobothrium latum from some freshwater fishes of central Canada

Two species of Diphyllobothrium occurred in Quigly Lake, Manitoba: plerocercoids of D. dendriticum encapsulated on the viscera of shallow water cisco (Coregonus artedii) and lake whitefish (Coregonus clupeaformis) and plerocercoids of D. latum unencapsulated in the muscle of walleye (Stizostedion vitreum vitreum) and northern pike (Esox lucius). Adult D. dendriticum were obtained through experimental infections of both herring gulls (Larus argentatus) and hamsters (Mesocricetus auratus), but adult D. latum developed experimentally only in the latter. The scolex position of adult D. dendriticum was more anterior than D. latum in the small intestine of hamsters. Eggs were present in utero and in the faeces by days 10–11 postinfection (PI) for D. dendriticum in hamsters and gulls and by day 17 PI for D. latum in hamsters. Adult D. dendriticum grew longer and had more segments in gulls than in hamsters. The neck length of adult D. latum was at least five times greater than the neck length of adult D. dendriticum in hamsters by day 17 PI. Viewed laterally, the seminal vesicle in adult D. dendriticum was dorsal to the cirrus sac, while in D. latum, the seminal vesicle was dorsocaudal to the cirrus sac. A constriction between segments was noted for adult D. latum only.

Influence of bile acid structure on bile flow and biliary lipid secretion in the hamster.

A comprehensive study of the influence of bile acid structure on bile flow and biliary lipid secretion was carried out by infusing pure bile acids at a physiological rate into the proximal small intestine of a bile fistula hamster. Twelve individual bile acids, cholate (C), ursocholate (UC), chenodeoxycholate (CDC), and ursodeoxycholate (UDC) as their glycine (G), taurine (T), or unconjugated form, were studied so that influence of the hydroxy substituents as well as side-chain structure could be defined. The pattern of bile acid output was dependent on bile acid structure and reflected the site and rate of intestinal absorption. Conjugated bile acid output was delayed because of late ileal absorption, and TUC was poorly absorbed. Unconjugated trihydroxy bile acids, C and UC, also exhibited a delay in absorption, while CDC and UDC were absorbed immediately and achieved the highest bile acid output. Unconjugated bile acids were conjugated initially mostly with taurine and then mostly with glycine. The effect of glycine conjugates of each bile acid on bile flow and biliary lipid secretion was similar to that of their corresponding taurine conjugates. All conjugated bile acids induced a similar rate of bile flow (9-15 microliter bile/mumol bile acid), but unconjugated bile acids other than C induced more flow (20-25 microliter bile/mumol bile acid) than their corresponding conjugates. Conjugates of the dihydroxy bile acids induced a greater secretion of phospholipid and cholesterol than cholyl conjugates, whereas conjugates of UC were unique in inducing extremely low phospholipid and cholesterol secretion. For an increase of 1 mumol X min-1 X kg-1 in bile acid output, the increase in phospholipid secretion was 0.072 mumol X min X kg for GCDC and TCDC; 0.051 mumol X min-1 X kg-1 for GUDC and TUDC; and 0.030 mumol X min-1 X kg-1 for GC and TC. Increase in cholesterol output per mumol X min-1 X kg-1 of bile acid output was 0.013 mumol X min-1 X kg-1 for GCDC and TCDC, 0.011 mumol X min-1 X kg-1 for GUDC and TUDC, and 0.005 mumol X min-1 X kg-1 for GC and TC. In general, unconjugated bile acids induced more phospholipid and cholesterol than their corresponding conjugates; however, the rank-order effect of the steroid nucleus substituents was similar to that observed for the respective conjugates. These results indicate that both nuclear and side-chain structure influence the enterohepatic circulation and biliary secretory properties of bile acids.(ABSTRACT TRUNCATED AT 400 WORDS)

Hamster intestinal disaccharide absorption: extracellular hydrolysis precedes transport of the monosaccharide products.

Hydrolase-related transport was re-investigated in hamster small intestine by the tissue accumulation method. The Na+-dependent, phlorizin-sensitive monosaccharide transport system saturates with 30 mM-D-glucose. According to the hydrolase-related transport hypothesis, additional glucose units will be taken up if they are given in the form of a disaccharide susceptible to hydrolysis. But in experiments with [14C]sucrose we found no evidence for any such surplus glucose uptake. The uptake of 14C label from sucrose was abolished by using Tris, a strong inhibitor of sucrase, by adding competitive inhibitors of the D-glucose transport system (D-glucose, beta-methyl-D-glucopyranoside or phlorizin), and by substituting Li+ for the Na+ in the incubation medium. Glucose and fructose derived from sucrose did not enter the tissues in equimolar amounts: the glucose moiety was taken up much faster. We conclude that in hamster intestine there is no evidence for the existence of hydrolase-related transport with sucrose as the monosaccharide donor. The enzymatic hydrolysis of sucrose and the transport of its products, glucose and fructose, are two distinct events, acting sequentially.

The effect of cortisol on stimulation of enzymatic activity and absorption of amino acids in the small intestine of adult hamsters

1. 1. The s.c. administration of cortisol to hamsters (50 mg/kg body wt/day for 4 days) produces a significant increase in maltase sucrase, alkaline phosphatase and leucineaminopeptidase activity in intestinal mucosa. 2. 2. Lactase activity is unaffected by cortisol. 3. 3. Gamma-glutamyltranspeptidase activity increases slightly in females but remains unchanged in males. 4. 4. Cortisol causes increase in proline and glycine absorption without changing the absorption of lysine.

Quantitative and immunocytochemical studies of APUD cells in airways and gut. The effects of priming with L-dopa and 5-HTP.

The amine precursor uptake and decarboxylase (APUD) cells in airways and small intestine of adult hamsters have been studied by quantitative, histochemical and immunocytochemical methods for the presence of argyrophilia, ACTH, hGH, calcitonin, bombesin and prolactin in control animals and following priming with two amine precursors: L-dopa and 5-hydroxytryptophane (5-HTP). APUD cells have been defined by the presence of intracytoplasmic argyrophilic granules. A method that related them to airway or gut perimeter length or total epithelial cell numbers has been applied. Calcitonin-like-immunoreactivity (CLIR) is present in epithelial cells in the tracheal epithelium and glands. The presence of ACTH, hGH, bombesin or prolactin is not detected. Priming with L-Dopa and 5-HTP results in up to 12 fold increases in densities of argyrophilic APUD cells in airways and ileum when ratios of APUD cells/100 nuclei are compared to those in control animals. Exposure to 5-HTP induces no significant changes in densities of cells with CLIR in the trachea but CLIR is not detected in animals exposed to L-DOPA. Ratios of APUD cells/100 epithelial cells appear to be more sensitive than those of APUD cells/mm in detecting significant changes in APUD cell densities. Priming with amine precursors is a valuable tool in quantitative studies of neuroendocrine cells.

Mammalian small intestinal phytase (EC 3.1.3.8).

Phytase (EC 3.1.3.8) concentration has been measured in the small intestine of rat, rabbit, guinea-pig and hamster. Levels varied from 0.12 units (microgram phosphorus released/min)/mg protein in the rat to 0.03 units/mg protein in the rabbit. The enzyme is localized in the brush border of the small intestine of the rat. It is suggested that the levels and location of phytase are an important factor in the uptake of metals from metal-phytate complexes. Metal ions released in the immediate vicinity of the absorptive surface of the intestine could be absorbed before being rendered insoluble by competing reactions such as hydrolysis.

Sites of dipeptide hydrolysis in relation to sites of histidine and glucose active transport in hamster intestine.

The effects of dipeptides and amino acids on the active transport of L-histidine and D-glucose by sacs of everted small intestine of the hamster have been used to determine the sites of final hydrolysis of the dipeptides in relation to the sites of active transport of L-histidine and D-glucose. The results, plus earlier observations (Wiseman, 1977), show that (a) dipeptide active transport occurs at a superficial site, followed by progressively deeper sites for (b) final hydrolysis of glycyl-phenylalanine and phenylalanyl-glycine, then deeper (c) L-histidine active transport, then (d) final hydrolysis of alanyl-alanine, alanyl-leucine, glycyl-alanine, glycyl-proline, leucyl-alanine and leucyl-leucine, then (e) D-glucose active transport, then (f) final hydrolysis of alanyl-glycine, alanyl-valine, glycyl-glycine, prolyl-glycine, valyl-alanine and valyl-valine. The site of D-glucose active transport (2e) and all the sites superficial to it (2a-d) lie in the intestinal epithelial cell's brush-border. The location within the cell of site(s) 2f is not known; it may lie in the cytosol. All the dipeptides appeared to inhibit L-histidine active transport by the release of free amino acid and not by action of intact dipeptide, supporting the view that dipeptides and free amino acids do not share a common transport pathway in the epithelium of the small intestine.

Growth, Digestibility and Enzymatic Activities in the Pancreas and Intestines of Hamsters Fed Raw and Heated Soy Flour

The nutritional effects of feeding raw and heated soy flour to young golden Syrian hamsters were investigated over a period of 32 days. Those animals fed raw soy flour grew much more poorly than those fed heated soy flour, an effect which was reflected in a lower food efficiency as well. Growth retardation of hamsters fed raw soy flour was accompanied by a lower apparent digestibility of the protein (54%) compared to heated soy flour (76%). The pancreases of animals fed raw soy flour were increased in size and had elevated levels of trypsin, chymotrypsin, amylase, and lipase. With the exception of trypsin activity in the small intestine, similar differences in enzyme activities between the raw and heated soy groups were generally found in the small intestine, cecum, large intestine, and feces. There was, however, a progressive decrease in these activities in the lower regions of the intestinal tract and feces. It is concluded that the hamster, in common with several other species of animals, is sensitive to the effects of the trypsin inhibitors in raw soy flour, and may provide a useful model for studying the long-term effects of trypsin inhibitors on the pancreas.

Virtual elimination of the interference of unstirred water layers on intestinal sugar transport kinetics by use of the tissue accumulation method at appropriate shaking rates

The intestinal transport of sugars and amino acids seems to follow Michaelis-Menten kinetics, but the presence of unstirred water layers at the outer face of the brush border membrane may distort kinetic measurements. According to current theory, the capacity parameter, Jmc max would not be affected, but the Kt would be increased to a higher value, Kt ', in proportion to the thickness of the unstirred water layer, d. We reasoned that by increasing the shaking rate in the tissue accumulation method, d might drop to such small values that Kt ' would fall to a constant level practically equal to the "true" Kt. We measured D-galactose influx into rings of everted hamster intestine as a function of both the substrate concentration and the shaking rate. Our results show that as the circular stirring rate increases from 0.38--6.2 Hz, J mc max remains constant, as expected, but Kt ' first drops, then levels off to reach a plateau between 2 and 6.2 Hz. We conclude that the average Kt values in this frequency range (Kt = 7.4 mM) represent the true transport Kt. Furthermore, all previous kinetic work performed in our laboratory has been carried out under identical conditions, including shaking rates of 4 Hz. The validity of our preceding results is thus upheld.

Divalent cations and vitamin B12 uptake by intestinal brush-border membrane vesicles.

Brush-border membrane vesicles from hamster intestine were employed to investigate uptake (binding) of vitamin B12 (B12). Ileal vesicles took up 25 times more B12 than did jejunal vesicles. Uptake of B12 by ileal vesicles was dependent on intrinsic factor (IF) and required Ca2+. Increasing the Ca2+ concentration caused an increase in uptake of B12 reaching a maximum at approximately 8 mM Ca2+. At high Ca2+ concentrations, 6-8 mM, Mg2+ had little effect on uptake of B12. At low Ca2+ concentrations, up to 2 mM, Mg2+ stimulated B12 uptake. Mg2+, Mn2+, and, to a lesser extent, Sr2+ stimulated Ca2+-dependent B12 uptake, but Zn2+, Ba2+, Na+, K+, and La3+ did not. B12 was apparently not metabolized and was bound as IF-B12 complex, which could be removed with (ethylenedinitrilo)tetraacetic acid (EDTA). Our results suggest that two types of divalent cation reactive sites are involved in binding of IF-B12. One is Ca2+ specific. The other is less specific reacting with Mg2+, Mn2+, Sr2+, and perhaps Ca2+ itself, thereby stimulating Ca2+-dependent binding of IF-B12 to its ileal receptor.

Kinetics of uptake of lysine and lysyl-lysine by hamster jejunum in vitro.

1. The kinetics of 2-min uptake of L-lysine and L-lysyl-L-lysine have been studied by using rings of everted hamster intestine in vitro, and values for Kt and Vmax. established. 2. On a molar basis, mediated uptake was more rapid for the amino acid than for the peptide. Non-mediated uptake was more rapid for the peptide than for the amino acid. 3. Comparison of relative rates of uptake of lysine from equivalent solutions of lysine and lysyl-lysine showed that at low concentrations, uptake of lysine was less rapid from the peptide than from the amino acid, whereas at high concentrations, uptake of lysine was more rapid from the peptide than from the amino acid. This type of effect of concentration on relative rates of uptake from equivalent solutions of amino acid and peptide has not previously been described.

A hydrolase-related transport system is not required to explain the intestinal uptake of glucose liberated from phlorizin

The fate of [ 3H]glucose released from a wide range of [ 3H]phlorizin concentrations by phlorizin hydrolase has been studied under conditions where the Na +-dependent glucose transport system in hamster intestine is profoundly inhibited by the glucoside. At 0.2–2.0 mM phlorizin, the [ 3H]glucose uptake was a constant 11–12% of that generated by the enzyme and at the highest level, it was reduced to that of passive diffusion. Glucose liberated from 0.2 mM [ 3H]phlorizin is accumulated at a rate nearly equal to that found for 0.2 mM [ 14C]glucose when this free sugar uptake is measured in a medium containing 0.2 mM unlabeled phlorizin. Furthermore, without sodium, the accumulation rates of hydrolase-derived or exogenous glucose are both reduced to the rate of [ 14C]mannitol. Our results indicate that the glucose released from phlorizin enters the tissue via the small fraction of the Na +-dependent glucose carriers which escape phlorizin blockade together with a mannitol-like passive diffusion. It enjoys a kinetic advantage for tissue entry over free glucose in the medium by virtue of the position of the site where it is formed, i.e. inside the unstirred water layer and near normal entry portals. No special hydrolase-related transport system, like the one proposed for disaccharides, needs to be considered to account for our findings.

The kinetic advantage for transport into hamster intestine of glucose generated from phlorizin by brush border β-glucosidase

Phlorizin, labeled with tritium only in the glucose moiety, was used as substrate for the β-glucosidase present in brush border membranes from hamster intestine in order to study, simultaneously, the kinetics of hydrolysis and the fate of the [ 3H]glucose liberated by the enzyme. The [ 3H]glucose seems to experience the same hydrolase related transport into the intestinal villi as the hexoses liberated from the common disaccharides by their respective hydrolases. The released [ 3H]glucose accumulation rate is only partially inhibited by unlabelled glucose added to the medium as either the free sugar or as the precursors sucrose, lactose or glucose 1-phosphate, and then only when these sugars are present at very high levels. Furthermore, glucose oxidase, added to the medium as a glucose scavenger, has no effect on the uptake rate of the phlorizin hydrolase-liberated sugar. These and other findings are presented as evidence that, under conditions where the Na +-dependent glucose carrier is more than 97% inhibited by phlorizin, the glucose derived from the inhibitor, like the hexoses from disaccharides, has a kinetic advantage for transfer into the intestinal tissue.