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PubMed1981

Iron availability and absorption in rats fed sodium phytate.

Effects of dietary sodium phytate on iron availability and absorption in rats were assessed in two experiments. In the first experiment, iron-deficient rats were switched to diets containing variable levels of added sodium phytate and variable levels of iron as ferrous sulfate. Iron availability was evaluated by measuring hemoglobin regeneration after 2 weeks of feeding these diets. In the second experiment, both iron-adequate and iron-deficient rats were force-fed a slurry containing an iron-deficient diet, 59Fe and sodium phytate. Iron absorption was assessed by measuring the percentage of the 59Fe dose retained by the rats after 9 days. The results of the first experiment indicated that levels of dietary phytate up to 4% of the diet do not impair hemoglobin regeneration by anemic rats. The results of the second experiment indicated that sodium phytate does not affect iron absorption differently in iron-adequate rats compared to iron-deficient rats. It is suggested that conflicting results in the literature on effects of phytate on iron absorption may be explained by differences in experimental conditions or by the presence in the diet of some inhibitory component besides phytate, possibly dietary fiber.

Absorption↗

PubMed1993

Pyridoxine-5'-beta-D-glucoside: metabolic utilization in rats during pregnancy and availability to the fetus.

Pyridoxine-5'-beta-D-glucoside (PNG), which is abundant in various plant-derived food products, has been shown to be poorly utilized in male rats and adult men. To assess the metabolic utilization of PNG during pregnancy and the availability to the fetus, [3H]PNG and [14C]pyridoxine (PN) were orally administered to 15-d pregnant rats for direct assessment of the intestinal absorption, tissue distribution, and urinary excretion of the radioisotopes. The level of 3H was significantly greater in the liver, and urinary excretion of 3H tended to be lower than that of 14C. The relative distribution of 3H among the groups of B-6 vitamers within the liver was similar to that for 14C. There was greater uptake by the fetus of 3H than of 14C. There was no difference in the relative concentrations of 3H and 14C among the groups of B-6 vitamers within the fetus. Results of this study suggest that the metabolic utilization of PNG is similar to that of PN during pregnancy. Therefore, the availability of vitamin B-6 derived from maternal PNG seems to be similar to that of vitamin B-6 derived from maternal PN.

Administration, Oral↗

PubMed1996

The Caco-2 cell culture system can be used as a model to study food iron availability.

To assess the usefulness of the Caco-2 cell culture system as a model to study the availability of dietary iron, preliminary experiments were performed to determine the optimal conditions for iron uptake and transport. Iron uptake of radioactive ferrous sulfate was optimal at pH 5.5 using a 2:1 molar ratio of ascorbic acid to iron and a 1-h incubation time. Under these experimental conditions, we studied the effect on iron uptake of adding supernatants from homogenates of different meat sources, soybean protein isolates, egg albumen and bovine serum albumin. Iron uptake was 6.3 +/- 1.7% from meat, which was significantly greater (P < 0.001) than the values of 1.2 +/- 0.3% from soybean protein, 1.3 +/- 0.3% from egg albumen and 0.8 +/- 0.1% from bovine serum albumin. Iron uptake was also significantly higher from digested meat samples than from undigested meat when the protein concentration was equalized. Measurements of iron uptake and protein concentration from fractions obtained after preparative isoelectric focusing of meat and soybean protein extracts showed two peaks of higher protein concentration and iron uptake in meat, apparently not found in soybean protein, that contained the factor(s) responsible for the higher iron uptake by the cells. In view of these observed similarities with iron absorption studies in humans, we conclude that the Caco-2 cell culture system is a useful in vitro model to study food iron availability.

Ascorbic Acid↗

PubMed1999

Availability of food folate in humans.

The aim of our study was to determine whether the area-under-the-plasma-response-curve method with the positive area (AUC+) as primary analysis variable is suitable to evaluate the availability of food folate in humans. Healthy volunteers (n = 20) received four test meals in a randomized, four-period cross-over design as follows: meal A, 600 g spinach; meal B, 300 g spinach; meal C, 0.4 mg folic acid in water; meal D, folate-free control meal. Blood samples were drawn before administration of the test meals and up to 10 h postprandially. Plasma folate was significantly increased for up to 6 h after uptake of spinach and folic acid (P < 0.007), whereas the response curve after the control meal decreased slightly but significantly (P < 0.007). To calculate the net increase of plasma folate, the values were corrected by the individual predose concentrations. The AUC+ was calculated with these corrected values. The mean AUC+ was highest after consumption of meal A (71.2 +/- 24.0 h x nmol/L) followed by meal C (61.8 +/- 23. 8 h x nmol/L) and meal B (41.4 +/- 19.4 h x nmol/L). The AUC+ after meal B was significantly lower than after the other two meals (P < 0. 05). The results suggest that the AUC method with multiple blood sampling is useful for assessing the availability of food folate in humans.

Adult↗

PubMed2000

The metabolic availability of vitamin A is decreased at the onset of diabetes in BB rats.

Streptozotocin (STZ)-induced diabetic rats have been associated with an impaired metabolic availability of vitamin A (retinol). This study was undertaken to investigate whether Biobreeding (BB) rats, in which diabetes mellitus resembling human type I diabetes develops spontaneously, respond the same way at the onset of diabetes. Weaning diabetes-prone (BBdp) and normal (BBn) BB rats consumed NIH-07 nonpurified diet ad libitum until 120 d of age. Plasma and hepatic concentrations of retinol and its carriers, retinol-binding protein (RBP) and transthyretin (TTR) were lower in diabetic BB (BBd) rats than in BBn rats. In parallel with RBP, the abundance of mRNA was lower in the liver of BBd rats. Furthermore, the status of zinc, an important factor for the synthesis of RBP, was also disturbed in BBd rats, as indicated by lower circulatory levels and greater urinary excretion. To determine whether the biochemical evidence of vitamin A deficiency in BBd rats could be reversed, BBdp rats were fed a diet supplemented with vitamin A either alone or in combination with zinc. None of these treatments increased plasma vitamin A concentration. The hepatic abundance of RBP mRNA was significantly greater, whereas circulatory RBP concentrations were unaffected by vitamin A plus zinc supplementation. Overall, these results suggest that impaired metabolic availability of vitamin A, possibly caused by its decreased transport from hepatic stores, is another metabolic derangement associated with type I diabetes.

Animals↗

PubMed2003

Choline availability during embryonic development alters progenitor cell mitosis in developing mouse hippocampus.

Previously, we reported that dietary choline influences development of the hippocampus in fetal rat brain. It is important to know whether similar effects of choline occur in developing fetal mouse brain because interesting new experimental approaches are now available using several transgenic mouse models. Timed-pregnant mice were fed choline-supplemented (CS), control (CT) or choline-deficient (CD) AIN-76 diet from embryonic day 12 to 17 (E12-17). Fetuses from CD dams had diminished concentrations of phosphocholine and phosphatidylcholine in their brains compared with CT or CS fetuses (P < 0.05). When we analyzed fetal hippocampus on day E17 for cells with mitotic phase-specific expression of phosphorylated histone H3, we detected fewer labeled cells at the ventricular surface of the ventricular zone in the CD group (14.8 +/- 1.9) compared with the CT (30.7 +/- 1.9) or CS (36.6 +/- 2.6) group (P < 0.05). At the same time, we detected more apoptotic cells in E17 hippocampus using morphology in the CD group (11.8 +/- 1.4) than in CT (5.6 +/- 0.6) or CS (4.2 +/- 0.7) group (P < 0.05). This was confirmed using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin anti-digoxigenin fluorescein conjugate antibody nick end-labeling (TUNEL) and activated caspase-3 immunoreactivity. We conclude that the dietary availability of choline to the mouse dam influences progenitor cell proliferation and apoptosis in the fetal brain.

Animals↗

PubMed2006

Synchronizing the availability of amino acids and glucose decreases fat retention in heavy preruminant calves.

Effects of synchronizing the availability of amino acids and glucose within a day on protein and energy metabolism were studied in heavy preruminant calves. Thirty-six preruminant calves (148 +/- 1.6 kg body weight) were assigned to 1 of 6 degrees of nutrient synchrony (SYN, 1-6) and to 1 of 2 meal sequences (i.e., the high-protein meal in the morning or in the evening). Calves at SYN 1 received 2 balanced meals: one at 0600 and one at 1800. Nutrient synchrony decreased stepwise from SYN 1 to SYN 6 in which calves received 85% of the daily protein supply in 1 meal. The digestible energy intakes at 0600 and 1800 were equal between treatments. Daily intakes of all nutrients and dietary ingredients were identical for all treatments. Calves were housed individually in respiration chambers. Apparent fecal nutrient digestibility and nitrogen and energy balances were measured. Apparent nutrient digestibility decreased when >71% of the dietary protein was fed in one meal. Nutrient synchrony did not affect the efficiency of digestible protein utilization in calves at a identical digestible nutrient intake. Heat production decreased from 691 to 629 kJ/(kg(0.75) x d) (P < 0.05) and energy retained as fat increased from 116 to 184 kJ/(kg(0.75) x d) (P < 0.01) with decreasing nutrient synchrony. Meal sequence did not affect any of the traits. In conclusion, synchronizing the availability of amino acids and glucose within a day did not increase the efficiency of protein utilization but substantially decreased fat retention in heavy preruminant calves.

Adipose Tissue↗

PubMed2001

Helicobacter pylori infection reduces systemic availability of dietary vitamin C.

OBJECTIVE: Helicobacter pylori infection is recognized to lower the concentration of vitamin C in gastric juice. The objective of this study was to assess the effect of the infection on the systemic availability of dietary vitamin C. METHODS: The study involved 1,106 men and women aged 25-74 randomly recruited from the population of north Glasgow. Their H. pylori status, dietary vitamin C intake calculated from a food frequency questionnaire and plasma vitamin C concentration were measured. Correction was made for potential confounding factors such as age, sex, smoking and social status. RESULTS: The mean plasma vitamin C concentration in those who were H. pylori-positive was only 65% of that in those classified negative. Although partly explained by differences in age, sex, social class, smoking and vitamin C intake, the systemic reduction was observed across almost all sub-groups after stratification. Correction for all these factors still gave a plasma vitamin C level for H. pylori positives which was only 80% of that for negatives (P < 0.0001). CONCLUSIONS: H. pylori substantially impairs the bio-availability of vitamin C. This, together with the reduced vitamin C intake of H. pylori-positive subjects, markedly reduces the plasma vitamin C level of infected subjects. The reduced circulating levels of vitamin C in H. pylori-infected subjects may contribute to the aetiology of gastric cancer, as well as other diseases associated with anti-oxidant deficiency.

Adult↗

PubMed2001

Regulation of amino acid transporters by amino acid availability.

There is growing recognition that amino acid availability has profound effects on many aspects of cell function, including the control of membrane transport mechanisms, cell signalling, and gene expression. The precise mechanisms by which amino acids are able to elicit control over such diverse processes have become the focus of intense investigation recently. One particular area that has seen considerable advances is the molecular characterization of amino acid transporters, including members of the System A family, which are known to be regulated by amino acid supply. Recent developments concerning how cells sense and signal amino acid availability, and how this process influences the expression and function of amino acid transporters, are reviewed here. Elucidating the molecular mechanisms of these events will be important in clarifying how amino acid transporters might be regulated during altered nutritional states, and will be crucial for the design of new strategies aimed at improving nutritional support.

Amino Acid Transport Systems↗

PubMed1987

Jejunal and ileal absorption of oxprenolol in man: influence of nutrients and digestive secretions on jejunal absorption and systemic availability.

1 Study I evaluated the absorption of oxprenolol in the ileum, compared to jejunum, in healthy volunteers by an intestinal perfusion technique. Around 80 mg of drug were delivered as a saline solution directly in the small bowel. 2 Samples taken 30 cm distally to the site of perfusion showed that 63% of perfused oxprenolol was absorbed in the jejunum and 48% in the ileum; the differences were significant. 3 The plasma concentration-time profiles were similar for the two perfusions. The AUC and Cmax values of free and conjugated oxprenolol for the jejunal perfusion were significantly lower than those of ileum. They showed large but consistent intersubject variations in the two treatments. 4 Study II investigated, using the same technique, the influence of nutrients and digestive secretions on jejunal absorption and systemic availability of this drug. A saline (in treatments A and B) or a nutrient (in treatment C) solution containing oxprenolol was perfused into the jejunum below a balloon either inflated (A) or deflated (B and C). 5 The disappearance rate of oxprenolol from the jejunum was unaffected by endogenous secretions. The mean amount of drug absorbed along a 30-cm jejunal segment accounted for 52 (A) and 57% (B) of the total amount perfused. The intestinal absorption rate was markedly increased in the presence of nutrients (mean amount absorbed 96% for C). 6 The change in the rate of disappearance from the intestine had no effect on the systemic availability of oxprenolol (mean AUC values 8740, 8250 and 8020 nmol l-1 h for A, B and C, respectively) or its elimination from plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Biological Availability↗

PubMed1993

The influence of orally deposited budesonide on the systemic availability of budesonide after inhalation from a Turbuhaler.

1. The aim of this pharmacokinetic study was to evaluate to what extent oropharyngeal deposition of drug contributes to the systemic availability of budesonide inhaled from a dry powder inhaler (Turbuhaler). 2. The design was a randomized cross-over study in eight children aged 7-13 years. The plasma concentrations of the two epimers of budesonide (22R and 22S) after inhalation of 1 mg budesonide from a Turbuhaler were compared with the plasma concentrations obtained when the absorption of the drug deposited in the oropharynx was blocked by drinking and rinsing the mouth with charcoal before and after the inhalation. 3. The plasma concentrations of budesonide were significantly reduced by the charcoal treatment (P < 0.01) and the area under the time vs plasma concentration curve 0-4 h was significantly reduced from 9.5 to 8.0 mmol l-1 h for 22S (P < 0.01) and from 7.6 to 5.7 mmol l-1 h for 22R (P < 0.01). 4. The plasma concentrations and the AUCs after both Turbuhaler administrations were markedly higher than those obtained in earlier studies using other inhalers suggesting a higher intrapulmonary deposition of drug after Turbuhaler treatment. 5. It is concluded that oropharyngeal deposition of drug accounts for about 20% of the total systemic availability of budesonide inhaled from Turbuhaler. Thus, the main contribution to the system comes from budesonide absorbed in the airways.

Administration, Inhalation↗

PubMed1986

Effect of ingesta on systemic availability of penicillins administered orally in dogs.

Six penicillin preparations were administered to six dogs of various types, both when the dogs were fasted and when fed a standard meal immediately before dosing. The preparations used were: amoxycillin tablets and drops, ampicillin tablets, penicillin V tablets, phenethicillin tablets and cloxacillin capsules. A Latin square design was employed with ampicillin and the two amoxycillin preparations, while three separate cross-over studies were done with penicillin V, phenethicillin and cloxacillin. Dose rates used were 50 mg/kg for cloxacillin, and 10 mg/kg for the others. A microbiological method was used to assay penicillin in blood samples taken at intervals after dosing. Values for peak plasma drug concentration (Cmax), the time at which it occurred (Tmax), and area under the curve (AUC) were obtained for each curve of drug concentration plotted against time. In fasted dogs, ampicillin showed poorer systemic availability than did amoxycillin, with Cmax and AUC values of less than half those of amoxycillin. The solid and liquid preparations of amoxycillin had similar bioavailability. Ingesta adversely affected the systemic availability of antibiotic from all preparations tested. With ampicillin and both amoxycillin preparations, there were reduced Cmax and AUC and prolonged Tmax, indicating slowed and diminished absorption. Feeding did not alter Tmax with the other drugs, but reduced the Cmax of penicillin V, phenethicillin and cloxacillin and the AUC of cloxacillin. It is suggested that, if minimal impairment of bioavailability by ingesta is desired, then the penicillins commonly administered by mouth (amoxycillin, ampicillin, penicillin V, phenethicillin, cloxacillin) should be given to dogs that are fasting.

Administration, Oral↗

PubMed1982

Systemic availability of acetylsalicylic acid in human subjects after oral ingestion of three different formulations.

Systemic availability of acetylsalicylic acid (ASA) in normal human subjects after oral ingestion of 1 g in three different formulations was determined by using high-pressure liquid chromatography for ASA assay. For an effervescent, a plain and a sustained release preparation systemic availabilities expressed in percent of the ingested dose were 16.9 +/- 3.2, 8.6 +/- 1.2 and 2.6 +/- 0.4%, respectively. All subjects had clearly measureable amounts of ASA in plasma after oral intake of a sustained release preparation with an average peak concentration of 15 mumol/l. Peak concentration after an effervescent and plain formulation was on the average 80 and 40 mumol/l, respectively. Half-life of ASA in plasma was 18.1 +/- 1.2 min. for the effervescent and 28.7 +/- 5.3 min. for the plain preparation, while the elimination phase was too ill defined for the sustained release formulation. Average plasma half-life of salicylic acid (SA) was similar after the three different administration forms with values between 3.0 and 3.7 hrs. Further, no difference in SA distribution volumes or amounts of SA absorbed was found. The present study demonstrates that oral ingestion of ASA in effervescent, plain and sustained release formulations gives rise to significant amounts of ASA in plasma. Concentrations found indicate that long-term antithrombotic therapy with ASA in a sustained release formulation may be possible.

Administration, Oral↗

PubMed1988

Possible relevance of steroid availability and breast cancer.

The as yet circumstantial evidence for a central role of estrogens in the promotion of human breast cancer is supported by many data. However, it has not been possible to identify breast cancer patients or women at risk by abnormally elevated estrogen levels in plasma. The concept of available, i.e., non-SHBG bound sex steroid seems to offer a better understanding than total serum steroid levels do. We demonstrated that sex steroid protein binding is decreased by free fatty acids. This finding may help to explain how the affluent Western diet and sedentary life style is related to high incidence rates of breast cancer. We have postulated that it is especially the central (abdominal) type of obesity which may increase sex steroid availability. This mechanism could be important already at the age of breast development when the sensitivity to promotion seems relatively great. It may also explain the increased incidence rates which are observed in Western industrialized countries after menopause. It seems likely that other endocrine-related cancer, such as endometrial or prostatic carcinomas are influenced in an analogous way.

Biological Availability↗

PubMed2002

Reduced glycogen availability is associated with an elevation in HSP72 in contracting human skeletal muscle.

To test the hypothesis that a decrease in intramuscular glycogen availability may stimulate heat shock protein expression, seven men depleted one leg of muscle glycogen the day before performing 4-5 h of exhaustive, two-legged knee extensor exercise at 40 % of leg peak power output. Subjects then rested for a further 3 h. Muscle biopsies were obtained from the depleted and control leg before, immediately after and 3 h into recovery from exercise. These samples were analysed for muscle glycogen, and HSP72 gene and protein expression. In addition, catheters were placed in one femoral artery and both femoral veins and blood was sampled from these catheters prior to exercise and at 1 h intervals during exercise and into recovery for the measurement of arterial-venous differences in serum HSP72. Plasma creatine kinase (CK) was also measured from arterial blood samples. Pre-exercise muscle glycogen content was 40 % lower in the depleted compared with the control leg and this difference was maintained throughout the experiment (P < 0.05; main treatment effect). Neither HSP72 gene nor protein expression was different pre-exercise. However, both HSP72 gene and protein increased (P < 0.05) post-exercise in the depleted leg, but not in the control leg. Exercise did not increase plasma CK concentrations and we were unable to detect HSP72 in the serum of any samples. These results demonstrate that while acute, concentric exercise is capable of increasing HSP72 in human skeletal muscle, it does so only when glycogen is reduced to relatively low levels. Hence, our data suggest that HSP72 protein expression is related to glycogen availability. In addition, because CK did not increase and we found no evidence of HSP72 in the venous effluent, our data suggest that skeletal muscle is impermeable to HSP72.

Adult↗

PubMed2002

Effects of reduced free fatty acid availability on skeletal muscle PDH activation during aerobic exercise. Pyruvate dehydrogenase.

This study investigated the effect of reduced free fatty acid (FFA) availability on pyruvate dehydrogenase activation (PDHa) and carbohydrate metabolism during moderate aerobic exercise. Eight active male subjects cycled for 40 min at 55% Vo(2 peak) on two occasions. During one trial, subjects ingested 20 mg/kg body mass of the antilipolytic drug nicotinic acid (NA) during the hour before exercise to reduce FFA. Nothing was ingested in the control trial (CON). Blood and expired gas measurements were obtained throughout the trials, and muscle biopsy samples were obtained immediately before exercise and at 5, 20, and 40 min of exercise. Plasma FFA were lower in the NA trial (0.13 +/- 0.01 vs. 0.48 +/- 0.03 mM, P < 0.05), and the respiratory exchange ratio (RER) was increased with NA (0.93 +/- 0.01 vs. 0.89 +/- 0.01, P < 0.05), resulting in a 14.5 +/- 1.8% increase in carbohydrate oxidation compared with CON. PDHa increased rapidly in both trials at exercise onset but was approximately 15% higher (P < 0.05) throughout exercise in the NA trial (2.44 +/- 0.19 and 2.07 +/- 0.12 mmol x kg wet muscle(-1) x min(-1) for NA and CON at 40 min). Muscle glycogenolysis was 15.3 +/- 9.6% greater in the NA trial vs. the CON trial but did not reach statistical significance. Glucose 6-phosphate contents were elevated (P < 0.05) in the NA trial at 30 and 40 min of exercise, but pyruvate and lactate contents were unaffected. These data demonstrate that the reduction of exogenous FFA availability increased the activation of PDH and carbohydrate oxidation during moderate aerobic exercise in men. The increased activation of PDH was not explained by changes in muscle pyruvate or the ATP/ADP ratio but may be related to a decrease in the NADH/NAD(+) ratio or an epinephrine-induced increase in calcium concentration.

Adult↗

PubMed2004

Reduced plasma FFA availability increases net triacylglycerol degradation, but not GPAT or HSL activity, in human skeletal muscle.

Intramuscular triacylglycerols (IMTG) are proposed to be an important metabolic substrate for contracting muscle, although this remains controversial. To test the hypothesis that reduced plasma free fatty acid (FFA) availability would increase IMTG degradation during exercise, seven active men cycled for 180 min at 60% peak pulmonary O(2) uptake either without (CON) or with (NA) prior ingestion of nicotinic acid to suppress adipose tissue lipolysis. Skeletal muscle and adipose tissue biopsy samples were obtained before and at 90 and 180 min of exercise. NA ingestion decreased (P < 0.05) plasma FFA at rest and completely suppressed the exercise-induced increase in plasma FFA (180 min: CON, 1.42 +/- 0.07; NA, 0.10 +/- 0.01 mM). The decreased plasma FFA during NA was associated with decreased (P < 0.05) adipose tissue hormone-sensitive lipase (HSL) activity (CON: 13.9 +/- 2.5, NA: 9.1 +/- 3.0 nmol.min(-1).mg protein(-1)). NA ingestion resulted in decreased whole body fat oxidation and increased carbohydrate oxidation. Despite the decreased whole body fat oxidation, net IMTG degradation was greater in NA compared with CON (net change: CON, 2.3 +/- 0.8; NA, 6.3 +/- 1.2 mmol/kg dry mass). The increased IMTG degradation did not appear to be due to reduced fatty acid esterification, because glycerol 3-phosphate activity was not different between trials and was unaffected by exercise (rest: 0.21 +/- 0.07; 180 min: 0.17 +/- 0.04 nmol.min(-1).mg protein(-1)). HSL activity was not increased from resting rates during exercise in either trial despite elevated plasma epinephrine, decreased plasma insulin, and increased ERK1/2 phosphorylation. AMP-activated protein kinase (AMPK)alpha1 activity was not affected by exercise or NA, whereas AMPKalpha2 activity was increased (P < 0.05) from rest during exercise in NA and was greater (P < 0.05) than in CON at 180 min. These data suggest that plasma FFA availability is an important mediator of net IMTG degradation, and in the absence of plasma FFA, IMTG degradation cannot maintain total fat oxidation. These changes in IMTG degradation appear to disassociate, however, from the activity of the key enzymes responsible for synthesis and degradation of this substrate.

Adult↗

PubMed2004

Enteroendocrine cells and 5-HT availability are altered in mucosa of guinea pigs with TNBS ileitis.

Enteroendocrine cells act as sensory transducers, releasing 5-HT and numerous peptides that are involved in regulating motility, secretion, and gut sensation. The action of mucosal 5-HT is terminated by a 5-HT reuptake transporter (SERT). In this study, we examined the hypothesis that ileitis leads to changes in enteroendocrine cell populations and mucosal 5-HT availability. Ileitis was induced in guinea pigs by intraluminal injection of 2,4,6-trinitrobenzenesulfonic acid and experiments were conducted 3, 7, and 14 days after treatment. The number of somatostatin, neurotensin, and 5-HT-immunoreactive cells increased at 3 and 7 days of ileitis, respectively, whereas no significant changes in the numbers of cholecystokinin, glucagon-like peptide-2, glucose-dependent insulinotropic peptide, and peptide YY-immunoreactive cells were observed. Chemical stimulation of the inflamed mucosa with sodium deoxycholic acid significantly increased 5-HT release compared with basal release. Mechanical stimulation of the mucosa potentiated the effect of the chemical stimuli at day 7. Epithelial SERT immunoreactivity was significantly reduced during the time course of inflammation. Thus changes in enteroendocrine cell populations and 5-HT availability could contribute to the altered motility and secretion associated with intestinal inflammation by disrupting mucosal signaling to enteric nerves involved in peristaltic and secretory reflexes.

Animals↗