Stimulation of proximal small intestinal mucosal growth by luminal polyamines

1991 ◽  
Vol 261 (3) ◽  
pp. G504-G511 ◽  
Author(s):  
J. Y. Wang ◽  
S. A. McCormack ◽  
M. J. Viar ◽  
L. R. Johnson
Keyword(s):  
Drinking Water ◽  
Oral Administration ◽  
Thymidine Incorporation ◽  
Growth Parameters ◽  
Jejunal Mucosa ◽  
Surrounding Environment ◽  
Small Intestinal ◽  
Mucosal Growth ◽  
Stimulation Of

The purpose of this study was to determine whether luminal polyamines stimulate intestinal mucosal growth in vivo. Rats received 2% alpha-difluoromethylornithine (DFMO) added to their drinking water throughout the experiment. The polyamines spermidine and spermine (3 mg each/100 g body wt) were given intragastrically in combined doses once at 9:30 A.M. and again at 5:30 P.M. Duodenal and jejunal mucosal ornithine decarboxylase (ODC) activity in the DFMO-treated rats was inhibited significantly for the duration of the study. DFMO also markedly decreased the rate of [3H]thymidine incorporation into DNA of duodenal and jejunal mucosa. The decrease in [3H]thymidine incorporation was significant 4 days and maximal 6 and 8 days after beginning treatment with DFMO. Decreased ODC activity and DNA synthesis were paralleled by decreases in total mucosal DNA, RNA, and protein content. Administration of the polyamines significantly reversed the effects of DFMO except the inhibition of ODC. In fact, there were no significant differences in mucosal growth parameters between the controls (without DFMO) and those treated with DFMO plus polyamines. Oral administration of spermidine and spermine at a dose of 4.5 mg each/100 g body wt for 6 days to rats not treated with DFMO increased the normal rate of mucosal growth in the duodenum and jejunum as well. Polyamine accumulation in IEC-6 cells was measured to determine whether it was altered by DFMO. IEC-6 cells took up [3H]putrescine and [3H]spermidine from their surrounding environment and the uptake was stimulated by serum. DFMO (5 mM) totally inhibited the increase in ODC activity but had no effect on the cellular uptake of polyamines in the presence of putrescine.(ABSTRACT TRUNCATED AT 250 WORDS)

Ornithine decarboxylase and mucosal growth in response to feeding

1986 ◽  
Vol 251 (2) ◽  
pp. G270-G274 ◽  
Author(s):  
K. Tabata ◽  
L. R. Johnson
Keyword(s):  
Drinking Water ◽  
Gastric Mucosa ◽  
Ornithine Decarboxylase ◽  
Gastrointestinal Mucosa ◽  
Total Inhibition ◽  
Mucosal Growth ◽  
Rapid Activation ◽  
Stimulation Of

The purpose of this study was to examine the role of ornithine decarboxylase (ODC) in the stimulation of the growth of gastrointestinal mucosa following feeding. Rats were divided into five groups: 1) fasted for 2 days, 2) fasted for 2 days and refed for 2 days, 3) fasted for 2 days and refed with the addition of 5% difluoromethylornithine (DFMO) to the drinking water, 4) normally fed, and 5) normally fed plus 5% DFMO in the drinking water. In general the results show a significant dissociation between ODC activity and growth of gastrointestinal mucosa in response to feeding. In the gastric mucosa, growth was inhibited by fasting and DFMO and stimulated by feeding, but there were no significant changes in ODC activity in any of the five groups. In the ileum ODC activity increased dramatically in refed rats and was essentially eliminated in rats fed DFMO. DFMO, however, had no effect on mucosal growth in fed rats and only prevented part of the trophic response to refeeding. The results in the colon were much the same as in the ileum, except that DFMO prevented even less of the trophic response to refeeding, despite total inhibition of ODC. These data suggest that polyamines necessary for growth of gastrointestinal mucosa following feeding are not supplied by the rapid activation of mucosal ornithine decarboxylase.

Orally administered IGF-I increases intestinal mucosal growth in formula-fed neonatal pigs

1996 ◽  
Vol 270 (5) ◽  
pp. R1085-R1091 ◽  
Author(s):  
D. G. Burrin ◽  
T. J. Wester ◽  
T. A. Davis ◽  
S. Amick ◽  
J. P. Heath
Keyword(s):  
Oral Administration ◽  
Peripheral Circulation ◽  
Intestinal Lumen ◽  
Recombinant Human Insulin ◽  
Igf Binding Proteins ◽  
Intestinal Growth ◽  
Neonatal Pigs ◽  
Igf I ◽  
Small Intestinal ◽  
Mucosal Growth

Our objective was to determine the potentially anabolic effects of orally administered recombinant human insulin-link growth factor I (rhIGF-I)on small intestinal growth in formula-fed neonatal pigs. Unsuckled neonatal pigs received formula or formula containing added rhIGF-I (3.5 mg.kg-1.day-1) from birth to 4 days of age. Pigs in both groups were fed 30 ml/kg formula every 2 h on day 1 and then every 4 h on days 2-4, and blood was sampled daily. Oral administration of rhIGF-I to formula-fed neonatal pigs increased small intestinal weight, protein, and DNA content,but not length. Jejunal and ileal villus height, but not crypt depth or muscularis thickness, also were increased by oral rhIGF-I administration. Neither the circulating concentration of IGF-I nor the IGF-binding proteins differed between control and oral rhIGF-treated pigs, suggesting that the absorption of orally administered rhIGF-I from the intestinal lumen into the peripheral circulation was limited. Our results demonstrate that oral administration of rhIGF-I during the first 4 days after birth significantly increased small intestinal mucosal growth in formula-fed neonatal pigs. These results suggest that oral administration of rhIGF-I may be a viable therapeutic approach to enhance intestinal growth in neonates.

Amiloride inhibits rat mucosal ornithine decarboxylase activity and DNA synthesis

1988 ◽  
Vol 254 (3) ◽  
pp. G408-G415
Author(s):  
M. G. Ulrich-Baker ◽  
P. Wang ◽  
L. Fitzpatrick ◽  
L. R. Johnson
Keyword(s):  
Epithelial Cell ◽  
Dna Synthesis ◽  
Ornithine Decarboxylase ◽  
Cell Membranes ◽  
Thymidine Incorporation ◽  
Jejunal Mucosa ◽  
Decarboxylase Activity ◽  
Gastrointestinal Mucosa ◽  
Fasted Rats ◽  
Stimulation Of

Refeeding fasted rats induces a dramatic trophic response in gastrointestinal mucosa and is associated with elevations in both the rate of DNA synthesis and ornithine decarboxylase (ODC) activity. The signal for these increases is unknown. Amiloride prevents cell alkalinization by blocking Na+-H+ exchange at apical epithelial cell membranes. In study 1, rats were fasted 48 h, treated with amiloride (0.5 to 500 mg/kg), and refed for 4 h. Refeeding increased ODC activities in the jejunal mucosa (X8) and liver (X19) but not in the oxyntic gland mucosa. In the jejunum, but not the liver, the activation of ODC was completely abolished by 100 mg/kg amiloride. In study 2, the rate of DNA synthesis was determined by measuring the rate of [3H]thymidine incorporation 16 h after refeeding. Refeeding resulted in significantly increased rates of DNA synthesis (dpm.microgram DNA-1.30 min-1) over fasted levels, and amiloride at 100 mg/kg significantly reduced the elevations in the jejunum and liver. In conclusion, amiloride inhibits the postprandial increases in jejunal ODC activity and DNA synthesis in the jejunum and liver. The results indicate that 1) the Na+-H+ antiport is essential to the increased ODC activity in the jejunum and the stimulation of DNA synthesis in the jejunum and liver after a meal and 2) increases in DNA synthesis and their suppression by amiloride are not necessarily linked to ODC activity.

scholarly journals Recombinant Saccharomyces cerevisiae Strain Expressing a Model Cytochrome P450 in the Rat Digestive Environment: Viability and Bioconversion Activity

2007 ◽  
Vol 73 (11) ◽  
pp. 3566-3574 ◽  
Author(s):  
G. Garrait ◽  
J. F. Jarrige ◽  
S. Blanquet ◽  
E. Beyssac ◽  
M. Alric
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Drug Delivery ◽  
Oral Administration ◽  
Digestive Tract ◽  
Drug Delivery Systems ◽  
Recombinant Yeast ◽  
Coumaric Acid ◽  
Recombinant Microorganisms ◽  
Small Intestinal

ABSTRACT An innovative “biodrug” concept, based on the oral administration of living recombinant microorganisms, has recently emerged for the prevention or treatment of various diseases. An engineered Saccharomyces cerevisiae strain expressing plant P450 73A1 (cinnamate-4-hydroxylase [CA4H] activity) was used, and its survival and ability to convert trans-cinnamic acid (CIN) into p-coumaric acid (COU) were investigated in vivo. In rats, the recombinant yeast was resistant to gastric and small intestinal secretions but was more sensitive to the conditions found in the large intestine. After oral administration of yeast and CIN, the CA4H activity was shown in vivo, with COU being found throughout the rat's digestive tract and in its urine. The bioconversion reaction occurred very fast, with most of the COU being produced within the first 5 min. The gastrointestinal sac technique demonstrated that the recombinant yeast was able to convert CIN into COU (conversion rate ranging from 2 to 5%) in all the organs of the rat's digestive tract: stomach, duodenum, jejunum, ileum, cecum, and colon. These results promise new opportunities for the development of drug delivery systems based on engineered yeasts catalyzing a bioconversion reaction directly in the digestive tract.

scholarly journals Intraluminal capsaicin does not affect fluid and electrolyte absorption in the human jejunum but does cause pain

Gut ◽  
1998 ◽  
Vol 43 (2) ◽  
pp. 252-255 ◽  
Author(s):  
J Hammer ◽  
H F Hammer ◽  
A J Eherer ◽  
W Petritsch ◽  
P Holzer ◽  
...  
Keyword(s):  
Abdominal Pain ◽  
Control Period ◽  
Animal Experiments ◽  
Sensory Nerves ◽  
Jejunal Mucosa ◽  
Occlusion Balloon ◽  
Electrolyte Absorption ◽  
Perfusion Studies ◽  
Stimulation Of

Background—Stimulation of sensory nerves with capsaicin regulates ion transport in the small intestine in animal experiments.Aim—To investigate whether sensory nerves that are stimulated by capsaicin administration influence fluid and electrolyte absorption in the human jejunum in vivo.Method—Intestinal perfusion studies were performed in 12 healthy subjects using a four lumen tube with a proximal occlusion balloon and a plasma-like electrolyte solution. After an initial control period, 5 (n = 3), 10 (n = 8), or 50 (n = 1) μg/ml capsaicin was added to the perfusate, and this was followed by a final control period. Rates of absorption of water, sodium, potassium, chloride, and bicarbonate were determined in a 30 cm segment of jejunum using a non-absorbable volume marker.Results—At all three concentrations of capsaicin there were no significant changes in water and electrolyte absorption as compared with control periods. Two subjects who received 10 μg/ml and the subject receiving 50 μg/ml experienced crampy abdominal pain.Conclusion—The results do not support the hypothesis that capsaicin sensitive afferent nerves are involved in the physiological regulation of net absorption or secretion across the human jejunal mucosa. Chemical stimulation of these nerves, however, gives rise to abdominal pain.

Kegiatan pembelajaran sebagai upaya dalam menstimulus perkembangan sosial-emosional anak usia dini

2020 ◽  
Vol 3 (1) ◽  
pp. 43-57
Author(s):  
Aghnaita Aghnaita ◽  
Ajeng Almira Salsabila ◽  
Camelia Hanik ◽  
Maulida Syafitri ◽  
Norhayani Norhayani ◽  
...  
Keyword(s):  
Early Childhood ◽  
Social Development ◽  
Emotional Development ◽  
Learning Activities ◽  
Primary Data ◽  
Social Emotional ◽  
Cultural Backgrounds ◽  
Childhood Education ◽  
Surrounding Environment ◽  
Stimulation Of

This study aims to determine the emotional social development of early childhood in Integrated Early Childhood Education Tarbiyatul Athfal UIN Antasari Banjarmasin as well as the form of learning activities undertaken as an effort to stimulate the emotional social development. The research method used is qualitative research on 6 children and learning activities that can stimulate children's emotional emotional development as primary data. Based on research conducted, the results obtained that the child's emotional social development tends to be unstable. Children often prefer to play alone. Nevertheless, children also begin to show interest in hanging out in the surrounding environment and doing play activities together. In addition, there are several factors influence, such as: social emotional experiences of children, gender differences, differences in family and cultural backgrounds, and parenting. While the form of learning activities that are pursued in the form of stimulation of children's emotional social development include: routine activities of reading Asmaul Husna and short surahs, filling in journals, playing indoor, and conducting learning activities. The activity was carried out through exemplary methods, sharing learning, and collaborative games.

Stimulation of ovarian progesterone secretion by oxytocin in vivo

1988 ◽  
Vol 117 (4_Suppl) ◽  
pp. S199-S200
Author(s):  
E. DIETRICH ◽  
K. RENTELMANN ◽  
W. WUTTKE
Keyword(s):  
Progesterone Secretion ◽  
Stimulation Of

A Nude Mouse Model as an in vivo Infectivity Assay for Cryptospomdiosis

1993 ◽  
Vol 27 (3-4) ◽  
pp. 65-68 ◽  
Author(s):  
B. H. Kwa ◽  
M. Moyad ◽  
M. A. Pentella ◽  
J. B. Rose
Keyword(s):  
Drinking Water ◽  
Mouse Model ◽  
Nude Mouse ◽  
Cryptosporidium Parvum ◽  
Nude Mice ◽  
Surface Waters ◽  
Nude Mouse Model ◽  
Infectivity Assay ◽  
Limiting Dilution

Cryptosporidium parvum is an important patliogen of diarrlieal disease which has been implicated in several outbreaks associated with contamination of surface waters. In monitoring for C. parvum in drinking water sources, it is important to asce tain the viability, and more importantly, the infectivity of low numbers of recovered oocysts. Groups of 10 Balb/C nude (nu/nu) mice, 4-8 weeks old at time of inoculation, were infected with C. parvum oocysts from naturally infected calves and purified using Sheather's sucrose gradients. Oocysts were counted using the Merifluor IFA kit (Meridian). Each group of 10 mice were infected with 1,10,100 and 1000 oocysts respectively. Numbers of oocysts per inoculation were determined by limiting dilution, and parallel inocula were counted microscopically to ascertain the accuracy of the dilutions. Two uninfected nude mice were kept in each cage to serve as controls. Mouse stools were collected every 4 days, concentrated using the Fekal Kontrate Concentration Kit (Meridian) and oocysts were counted with a UV microscope using the Merifluor IFA Kit (Meridian). Oocyst counts were expressed in terms of number of oocyst/g feces. Mice inoculated with 1000 oocysts began to shed oocysts on day 32, mice inoculated with 100 oocysts began to shed on days 44-48, mice inoculated with 10 oocysts began to shed on days 56-60, and mice inoculated with 1 oocyst shed on days 68-88. All infected mice continued to shed oocysts intermittently and with variable oocyst counts until day 180 when the experiment was terminated. This study established that it is possible to infect nude mice with very low numbers, down to a single oocyst. We are currently in the process of correlating the nude mouse assay with other viability assays.

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