JACKIE WOOD

..Investigative approaches to immuno-ENS interactions merge the disciplines of mucosal immunology and ENS neurophysiology into the realm of neurogastroenterology...

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..Integrative circuits in the ENS receive and interpret the chemical signals from the mast cells. Signals from the mast cells are interpreted by the ENS as a labeled code for the presence of a threat in the intestinal lumen...

..We review here the integrated systems of physiology and cellular neurobiology that are basic to understanding the actions of opioid agonists and antagonists in the digestive tract...

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..The symptom of explosive watery diarrhea becomes self-explanatory in this scenario...

..Progress in understanding mechanosensory detection in these processes, disordered enteric nervous system integration in diarrhea and constipation and pharmacotherapy is summarized...

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..Advances in this sphere are translating to improved insight into chronic functional abdominal and pelvic pain syndromes in general...

..This review details current concepts of the underlying pathophysiology in terms of the physiology of intestinal secretion, motility, nervous control, sensing function, immuno-neural communication, and the brain-gut axis...

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..Detection of anti-enteric neuronal antibodies in the serum of patients with early symptoms of a functional gastrointestinal motility disorder may prove to be a useful diagnostic test for inflammatory enteric neuropathy...

..Advances in understanding of the enteric nervous system (ENS) support the brain-in-the-gut concept. Progress relative to sensory neurons, reflex circuits and central pattern generators is summarized...

..This is postulated to underlie the secretory diarrhea and abdominal discomfort associated with stress...

..The results suggest that nociceptin acts both pre- and postsynaptically by activating an ORL(1) receptor that is distinct from typical naloxone-sensitive opioid receptors...

..The mucosa, submucosal blood vessels, and the circular muscle coat also showed P2X(7) receptor immunoreactivity...

..The P2Y1 receptor on the neurones was identified as a metabotropic receptor linked to activation of phospholipase C, synthesis of inositol 1,4,5-trisphosphate and mobilization of Ca2+ from intracellular stores...

..The 5-HT(2B) receptor subtype was not involved in actions at nicotinic synapses or stimulation of secretion...

..Anti-Hu immunostaining was judged to be an acceptable method for obtaining reliable estimates of total numbers of myenteric neurones in relation to other specific histochemical properties such as histamine binding...

..We conclude that histamine acts at the histamine H2 receptor subtype to stimulate adenylate cyclase and the formation of cAMP in myenteric ganglia of the guinea-pig small bowel...

..Nevertheless, details of the neural mechanism of action for Ucns have been unclear. We have, here, tested the hypothesis that Ucns act in the enteric nervous system (ENS) to influence colonic motor behaviour...

..However, galantide alone suppressed ICa. The results suggest two mechanisms of action for galanin: one is opening of inwardly rectifying potassium channels and the second is blockade of voltage-activated calcium channels...

..Burimamide, a histamine antagonist with higher activity at putative H3 receptors than H2 receptors, effectively reversed the inhibitory action of histamine on the excitatory postsynaptic potentials.(ABSTRACT TRUNCATED AT 250 WORDS)..

..5. The results add to existing evidence for expression of a functional P2Y(1) purinergic receptor in neurones of the submucosal division of the ENS...

..Adenosine also suppresses nicotinic cholinergic transmission by activating presynaptic high affinity Al receptors...

..Compared with synaptic behavior of small intestinal myenteric neurons, the notable differences were absence of the rundown phenomenon for fast EPSPs in the colonic neurons and a greater incidence of spontaneously occurring fast EPSPs...

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..Histamine, prostaglandins, and leukotrienes are paracrine signals in the communication pathway from mast cells to the small intestinal ENS...

..The mechanism of signal transduction involves stimulation of PLC and intraneuronal calcium mobilization and is independent of prostanoid formation...

..The receptor mediating these effects was distinct from currently recognized cysteinyl leukotriene receptor subtypes (CysLT(1) and CysLT(2) receptors) and may represent a new receptor subtype...

..Once formed and released, the prostaglandins act to elevate the excitability of ganglion cells in the myenteric plexus and to suppress the synaptic release of neurotransmitters...

..The evidence suggests that the galanin GAL1 receptor, but not the galanin GAL2 receptor, mediated the presynaptic and postsynaptic inhibitory actions of galanin...

..This review details current concepts for the underlying pathophysiology in terms of the physiology of intestinal secretion, motility, nervous control, sensing function, immuno-neural communication and the brain-gut axis...

..The results support ATP as a neurotransmitter for IJPs in the intestine and are consistent with the hypothesis that the P2Y(1) purinergic receptor subtype mediates the action of ATP...

..Absence of NF145 from ganglion cells in the submucosal plexus is an example of differences between myenteric and submucosal components of the enteric nervous system...

..The enhanced presence of norepinephrine is expected to suppress fast and slow excitatory neurotransmission in the enteric microcircuits and to suppress neurogenic mucosal secretion...

..Our evidence suggests that ATP is released as a neurotransmitter to stimulate neurogenic mucosal secretion by binding to P2Y1 receptors expressed by VIP-ergic secretomotor neurons...

..Continued focus on neurogastroenterologic factors that underlie the development of symptoms will lead to mechanistic understanding that is expected to directly benefit the large contingent of patients and care-givers who deal with FGIDs...

..Actions on enteric neurons might underlie the neural mechanisms by which stress-related release of CRF in the periphery alters intestinal propulsive motor function, mucosal secretion, and barrier functions...

..These results suggest a novel mechanism regulating the TRPV3 response to inflammation, which differs from TRPV1 and TRPV4, and involves a direct action of free fatty acids on the channel...

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..Pathophysiological significance of the excitatory actions on secretomotor neurons might be stimulated mucosal secretion and the secretory diarrhea associated with intestinal inflammatory states...

..beta-NAD meets the traditional criteria for a neurotransmitter that contributes to enteric inhibitory regulation of visceral smooth muscles...

..Our data suggest the existence of a common activation mechanism for TRPV1, TRPV2, and TRPV3 that may serve as a therapeutic target for pain management and treatment for diseases caused by hypersensitivity and temperature misregulation...

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..CRF(1)-IR was expressed in neuronal neighbors of those with CRF-IR. Collective evidence suggests that VIPergic secretomotor neurons might provide synaptic input to neighboring cholinergic neurons...

..The overall goal of the study is to better understand the role of bradykinin in motility disturbances, diarrhea, abdominal pain and inflammation. ..

..Dephosphorylation of the channels by the phosphatase, calcineurin, terminates slow EPSP. ..

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..The overall goal of the study is to understand better the neurophysiology underlying gastrointestinal immuno-neural communication and its involvement in the symptomatology of diarrhea, abdominal pain and intestinal inflammation. ..

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..These results are expected to improve understanding of neural determinants of motor function in the lower esophageal sphincter and in the proximal and distal stomach, as well as mechanisms of gastro-pyloro-duodenal motor coordination...