Sodium deoxycholate promotes the absorption of heparin administered orally,probably by acting on gastrointestinal mucosa,in rats

Summary Sodium deoxycholate (DOC), selected as a promoter of gastrointestinal absorption of heparin, was administered orally to rats, followed, at increasing intervals, by heparin. Maximal plasma clearing activity (PC) was obtained with a 60-min interval, though PC was still elicited after 24 h, suggesting that DOC acts on the gastrointestinal mucosa. Inhibition of blood coagulation was also observed after oral heparin. The suggestion that DOC increases heparin absorptions is supported by increased plasma levels of heparin. No signs of several gastrointestinal damage were seen.     

Sodium deoxycholate promotes the absorption of heparin administered orally, probably by acting on gastrointestinal mucosa, in rats

Sodium deoxycholate (DOC), selected as a promoter of gastrointestinal absorption of heparin, was administered orally to rats, followed, at increasing intervals, by heparin. Maximal plasma clearing activity (PC) was obtained with a 60-min interval, though PC was still elicited after 24 h, suggesting that DOC acts on the gastrointestinal mucosa. Inhibition of blood coagulation was also observed after oral heparin. The suggestion that DOC increases heparin absorption is supported by increased plasma levels of heparin. No signs of several gastrointestinal damage were seen.     

The role of conjugative transposons in spreading antibiotic resistance between bacteria that inhabit the gastrointestinal tract

There is huge potential for genetic exchange to occur within the dense, diverse anaerobic microbial population inhabiting the gastrointestinal tract (GIT) of humans and animals. However, the incidence of conjugative transposons (CTns) and the antibiotic resistance genes they carry has not been well studied among this population. Since any incoming bacteria, including pathogens, can access this reservoir of genes, this oversight would appear to be an important one. Recent evidence has shown that anaerobic bacteria native to the rumen or hindgut harbour both novel antibiotic resistance genes and novel conjugative transposons. These CTns, and previously characterized CTns, can be transferred to a wide range of commensal bacteria under laboratory and in vivo conditions. The main evidence that gene transfer occurs widely in vivo between GIT bacteria, and between GIT bacteria and pathogenic bacteria, is that identical resistance genes are present in diverse bacterial species from different hosts.     

Tachykinins and their functions in the gastrointestinal tract

In the gastrointestinal tract, tachykinins are peptide neurotransmitters in nerve circuits that regulate intestinal motility, secretion, and vascular functions. Tachykinins also contribute to transmission from spinal afferents that innervate the gastrointestinal tract and have roles in the responses of the intestine to inflammation. Tachykinins coexist with acetylcholine, the primary transmitter of excitatory neurons innervating the muscle, and act as a co-neurotransmitter of excitatory neurons. Excitatory transmission is mediated through NK1 receptors (primarily on interstitial cells of Cajal) and NK2 receptors on the muscle. Tachykinins participate in slow excitatory transmission at neuro-neuronal synapses, through NK1 and NK3 receptors, in both ascending and descending pathways affecting motility. Activation of receptors (NK1 and NK2) on the epithelium causes fluid secretion. Tachykinin receptors on immune cells are activated during inflammation of the gut. Finally, tachykinins are released from the central terminals of gastrointestinal afferent neurons in the spinal cord, particularly in nociceptive pathways. Received 24 March 2007; received after revision 30 August 2007; accepted 14 September 2007     

Modifications by Nematoda of the sensitivity of mice to Salmonella abortus ovis administered orally or subcutaneously]

Mice inoculated 6 to 9 days previously with Heligmosomoides polygyrus (=Nematospiroides dubius) become more frequently infected than controls after an oral challenge with a constant dose of Salmonella abortus ovis. But parasitism increases the LD 50 when the subcutaneous route of infection is used, probably by stimulating the immune system of the host.     

Development of enterochromaffin and dopamine cells in the gastrointestinal tract of the calf

Zusammenfassung Nachweis der ersten enterochromaffinen and dopaminen Zellen im Magendarmtraktus des Rindes während der 6. und 7. Woche der Embryonalentwicklung. Die Differenzierung der beiden Zelltypen gelang leicht mittels Fluoreszenz (Formaldehyd), topographischer Verteilung und Zellstruktur. Während die enterochromaffinen Zellen aus den Darmepithelzellen stammen, scheint es sich bei den dopaminen Zellen um Mastzellen zu handeln.

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This study was supported by a grant from the National Research Council for Medical Sciences of Finland and the Sigrid Jusélius Foundation.     

The distribution of argentaffin cells in the gastrointestinal tract of the sulfamerazine treated rat

Zusammenfassung Eine direkte Korrelation zwischen Serotoninspiegel und der Zahl der argentaffinen Zellen im gastro-intestinalen Trakt normaler Ratten und solcher, die nach Sulfamerazinbehandlung einen höheren Serotoninspiegel aufweisen, wird festgestellt.

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This research was supported by research grants from the National Science Foundation, (No. GB 6105), and from the American Medical Association Education and Research Foundation awarded toJ. H. Thompson. Dr.M. A. Verity kindly prepared the slides.     

Pressor and oxitocic-like effects of angiotensin affected by aldosterone pretreatment in guinea-pigs

Résumé Les auteurs examinent l'augmentation de l'action de l'angiotensine sur la pression carotidienne et sur la contraction utérine chez des animaux traités avec de l'aldostérone. Ils pensent aussi que le traitement conditionne le développement du phénomène taquiphylactique de l'angiotensine.     

A correlation between the ability to withstand high temperatures and radioresistance inDrosophila melanogaster

Résumé Dans une étude sur 18 races deD. melanogaster une corrélation a été trouvée entre les facultés de résistance aux températures élevées et à l'irradiation du Co⁶⁰.     

The effect of pentagastrin on the A1-cells of the pancreatic islets in guinea-pigs

Zusammenfassung Meerschweinchen wurden für 5 Tage mit Pentagastrin injiziert und die Kerngrössen in den Pankreas-Inseln mit Karyometrie bestimmt. Die Kerne der A₁-Zellen nahmen in den behandelten Tieren am Anfang ab und schienen kleiner als in den Kontrollen. In den A₂-und B-Zellen wurden keine Veränderungen nach Pentagastrin notiert. Die Resultate stützen die Auffassung, dass Gastrin in den A₁-Zellen produziert wird.

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The work was supported by grants from the Swedish Medical Research Council No. B70-2297-03. The pentagastrin (Peptavlon) was kindly supplied by Imperial Chemical Industries (ICI).