Richard A. Borman

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1. 5-Hydroxytryptamine (5-HT) is known to produce a number of different effects in the gastrointestinal tract of various species, and has been proposed to play a key role in a number of intestinal disorders in man, including irritable bowel syndrome (IBS), although the receptors involved have yet to be established. The aim of the present study was to(More)
ACE 2, a novel homologue of angiotensin converting enzyme, has recently been identified. This study used QRT-PCR to quantitatively map the transcriptional expression profile of ACE 2 (and the two isoforms of ACE) in 72 human tissues. While confirming that ACE 2 expression is high in renal and cardiovascular tissues, the novel observation has been made that(More)
BACKGROUND AND PURPOSE Lubiprostone (Amitiza), a possible ClC-2 channel opener derived from prostaglandin E(1) and indicated for the treatment of constipation, increases chloride ion transport and fluid secretion into the intestinal lumen. As lubiprostone may also directly modulate gastrointestinal motility, we investigated its actions and the possible(More)
In conclusion, application of 5-HT has been shown to induce fluid secretion in both the small and large intestine of man. By the use of selective antagonists, the receptors mediating these effects have been identified and characterized. 5-HT induces secretion across human ileal mucosa via a receptor of the 5-HT4 sub-type, whereas a receptor of the 5-HT2A(More)
BACKGROUND Prostaglandin E(2) (PGE(2) ) is an inflammatory mediator implicated in several gastrointestinal pathologies that affect normal intestinal transit. The aim was to establish the contribution of the four EP receptor types (EP(1-4) ), in human colon, that mediate PGE(2) -induced longitudinal smooth muscle contraction. METHODS Changes in isometric(More)
In conclusion, 5-HT has been shown to contract both circular and longitudinal muscle layers of human terminal ileum. By the use of selective antagonists, the receptors mediating these actions have been identified. In the circular muscle of human small intestine, 5-HT-induced contraction is mediated via a receptor of the 5-HT1D sub-type, whereas a receptor(More)
There is an urgent clinical need for a safe, efficacious stimulant of gastric emptying; current therapies include erythromycin (an antibiotic with additional properties which preclude chronic use) and metoclopramide (a 5-hydroxytryptamine type 4 receptor agonist and an antagonist at brain D2 receptors, associated with movement disorders). To move away from(More)
Adenosine is an endogenous nucleoside that regulates many physiological processes through the activation of its four receptors: A(1), A(2A), A(2B) and A(3). Previous studies have identified the involvement of A(2) receptors in the inhibitory activity of adenosine analogues on tumor necrosis factor-alpha (TNF-alpha) production by lipopolysaccharide (LPS)(More)
Cholera toxin-induced intestinal secretion inintact rats requires a functioning myenteric plexus. Theaim of this investigation was to determine whetherneural elements were essential for cholera toxin to produce a secretory effect in human isolatedileum. Mucosal preparations were mounted in Ussingchambers. Cholera toxin was applied apically andshort-circuit(More)
The aim of this study was to characterise the 5-HT receptor(s) mediating secretory responses of isolated human colonic mucosa to 5-HT. Sheets of muscle-stripped mucosa from proximal (ascending) and distal (sigmoid) human colon were set up in Ussing chambers for measurement of short-circuit current (Isc). Serosal application of 5-HT led to non-neural,(More)