Shaping research for people living with co-existing mental and physical health conditions: A research priority setting initiative from the United Kingdom.

INTRODUCTION: Those with severe and enduring mental ill health are at greater risk of long-term physical health conditions and have a reduced life expectancy as a result. Multiple factors compound this health inequality, and the need for setting research priorities in this area is highlighted with physical and mental healthcare services being separate, and limited multimorbidity research. METHODS: The aim of this exercise was to work in partnership with healthcare professionals and carers, family, friends and individuals with lived experience of both mental and physical health conditions, to set research priorities to help people with mental health conditions to look after their physical health. The exercise was guided by the James Lind Alliance approach. For this, a steering group was set up, two surveys were completed and a final priority workshop was conducted. RESULTS: This priority setting exercise guided by people's needs and lived experience has produced a set of well-defined research topics. Initially, 555 research questions were suggested in the first survey, which were refined to 54 questions for the second survey. A priority setting workshop was then conducted to get the final 10 priorities. CONCLUSIONS: Taking these topics forward to improve services and treatment for both mental and physical ill health may in turn improve physical health and lessen the reduced life expectancy of those living with mental ill health. PATIENT OR PUBLIC CONTRIBUTION: This work was completed in collaboration with people who have lived experience of mental ill health and physical health conditions, as well as carers, family and friends. Their contribution has been significant for this work from piloting surveys, amending language used and educating the researchers and contributing to this paper. The initial work was completed with a steering group and continued with surveys and workshops.

The overuse of intrapartum cardiotocography (CTG) for low-risk women: An actor-network theory analysis of data from focus groups.

BACKGROUND: There is an overuse of cardiotocography for intrapartum fetal monitoring for low-risk women in high-income countries, despite recommendations from evidence-based guidelines. AIM: To understand why midwives use cardiotocography for low-risk women despite evidence-based recommendations and to understand the roles of the cardiotocograph machine. METHOD: This qualitative study used focus groups for data collection. Thirty-one midwives and three student midwives participated from four different countries: New Zealand, Australia, Denmark, and Norway. Constant comparative analysis, informed by an actor-network theory framework, was the method of data analysis. FINDINGS: Cardiotocography was multifaceted and influenced all attendants in the birth environment. The cardiotocograph itself is assigned different roles within the complex networks surrounding childbirth. The cardiotocograph's roles were as a babysitter, the midwives' partner, an agent of shared responsibility, a protector that 'covers your back', a disturber of normal birth, and a requested guest. DISCUSSION: The application of the actor-network theory enabled us to understand how midwives perceive cardiotocography. The assigned roles of the cardiotocograph shape its everyday use more than evidence-based guidelines. Discussion of these inconsistencies must inform the use of cardiotocography in the care of women with low-risk pregnancies. CONCLUSION: We found that the cardiotocograph is a multifaceted actant that influences practice by performing different roles. Drawing on this study, we suggest that actor-network theory could be a helpful theoretical perspective to critically reflect upon the increasing use of technologies within maternity care.

The development and initiation of the NSW Department of Health interprofessional Fetal welfare Obstetric emergency Neonatal resuscitation Training project.

BACKGROUND: The Fetal Welfare Obstetric emergency Neonatal resuscitation Training (FONT) project was initiated on a background of rising notifications of adverse events in NSW maternity units, the significant proportion of which were related to fetal welfare assessment. AIMS: The aim of the study is to describe the development and introduction of the NSW state-wide interprofessional FONT project. METHODS: Following development and risk assessment, FONT was launched in February 2008. The project consists of an online component and two face-to-face training days to be completed each 3 years; the first day for fetal welfare assessment and the second for obstetric and newborn emergencies. Eight, 2-day training sessions were conducted throughout NSW for FONT trainers. Each trainer underwent pre- and post-testing for changes in knowledge of fetal welfare assessment. The 2005-2008 NSW adverse event report numbers were assessed. RESULTS: From 20 February to 17 April 2008, 240 trainers had been trained in fetal welfare assessment, and by the end of 2008 these trainers had trained 954 clinicians. There were significant improvements in the interpretation and management planning of electronic fetal heart rate patterns following training. Analysis of Severity Assessment Codes 1 and 2 showed no significant trend in the number of notifications for adverse events related to fetal welfare assessment. CONCLUSIONS: In the first 11 months, 25% of the state's maternity practitioners had received training in the first stage of the FONT project. The FONT project has shown short-term improvements in learning and communication skills and in the participants of the project.

Women's experiences of antenatal transfer for threatened premature labour in NSW: A qualitative study.

BACKGROUND: Each year thousands of pregnant women experiencing threatened premature labour are transferred considerable distances across Australia to access higher level facilities but only a small proportion of these women go on to actually give birth to a premature baby. Women from regional areas are required to move away from their home, children and support networks because of a perceived risk of birthing in a centre without neonatal intensive care facilities. AIM: This study examines the experience of women undergoing antenatal transfer for threatened premature labour in New South Wales and the Australian Capital Territory who do not give birth during their transfer admission. METHODS: Thirteen semi-structured in-depth interviews were held with women across five tertiary referral sites across New South Wales and the Australian Capital Territory, and analysed until saturation for themes. FINDINGS: Seven urban and six rural women were interviewed. Women and their families were all negatively affected by antenatal transfer. Factors that helped enable a positive experience were; enhanced sense of safety in the tertiary unit, and individual qualities of staff. Factors that contributed to negative experiences were; inadequate and conflicting information, and no involvement or choice in the clinical decision-making process to move to another facility. CONCLUSIONS: Antenatal transfer is an extremely stressful experience for women and their families. The provision of high quality written and verbal information, and the inclusion of women's perception of risk in the clinical decision making process will improve the experience for women and their families in NSW and the ACT.

Activation of adenosine low-affinity A3 receptors inhibits the enteric short interplexus neural circuit triggered by histamine.

We tested the novel hypothesis that endogenous adenosine (eADO) activates low-affinity A3 receptors in a model of neurogenic diarrhea in the guinea pig colon. Dimaprit activation of H2 receptors was used to trigger a cyclic coordinated response of contraction and Cl(-) secretion. Contraction-relaxation was monitored by sonomicrometry (via intracrystal distance) simultaneously with short-circuit current (I(sc), Cl(-) secretion). The short interplexus reflex coordinated response was attenuated or abolished by antagonists at H2 (cimetidine), 5-hydroxytryptamine 4 receptor (RS39604), neurokinin-1 receptor (GR82334), or nicotinic (mecamylamine) receptors. The A1 agonist 2-chloro-N(6)-cyclopentyladenosine (CCPA) abolished coordinated responses, and A1 antagonists could restore normal responses. A1-selective antagonists alone [8-cyclopentyltheophylline (CPT), 1,3-dipropyl-8-(2-amino-4-chlorophenyl)xanthine (PACPX), or 8-cyclopentyl-N(3)-[3-(4-(fluorosulfonyl)benzoyloxy)propyl]-xanthine (FSCPX)] caused a concentration-dependent augmentation of crypt cell secretion or contraction and acted at nanomolar concentrations. The A3 agonist N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) abolished coordinated responses and the A3 antagonist 3-ethyl-5-benzyl-2-methyl-4-phenylethynyl-6-phenyl-1,4-(+/-)-dihydropyridine-3,5-dicarboxylate (MRS1191) could restore and further augment responses. The IB-MECA effect was resistant to knockdown of adenosine A1 receptor with the irreversible antagonist FSCPX; the IC(50) for IB-MECA was 0.8 microM. MRS1191 alone could augment or unmask coordinated responses to dimaprit, and IB-MECA suppressed them. MRS1191 augmented distension-evoked reflex I(sc) responses. Adenosine deaminase mimicked actions of adenosine receptor antagonists. A3 receptor immunoreactivity was differentially expressed in enteric neurons of different parts of colon. After tetrodotoxin, IB-MECA caused circular muscle relaxation. The data support the novel concept that eADO acts at low-affinity A3 receptors in addition to high-affinity A1 receptors to suppress coordinated responses triggered by immune-histamine H2 receptor activation. The short interplexus circuit activated by histamine involves adenosine, acetylcholine, substance P, and serotonin. We postulate that A3 receptor modulation may occur in gut inflammatory diseases or allergic responses involving mast cell and histamine release.

Individualised and complex experiences of integrative cancer support care: combining qualitative and quantitative data.

OBJECTIVES: The widespread use of complementary therapies alongside biomedical treatment by people with cancer is not supported by evidence from clinical trials. We aimed to use combined qualitative and quantitative data to describe and measure individualised experiences and outcomes. MATERIALS AND METHODS: In three integrative cancer support centres (two breast cancer only) in the UK, consecutive patients completed the individualised outcome questionnaire Measure Yourself Concerns and Wellbeing (MYCaW) before and after treatment. MYCaW collects quantitative data (seven-point scales) and written qualitative data and the qualitative data were analysed using published categories. RESULTS: Seven hundred eighty-two participants, 92% female, mean age 51 years, nominated a wide range of concerns. Psychological and emotional concerns predominated. At follow-up, the mean change (improvement) in scores (n = 588) were: concern 1, 2.06 (95% CI 1.92-2.20); concern 2, 1.74 (95% CI 1.60-1.90); and well-being, 0.64 (95% CI 0.52-0.75). The most common responses to 'what has been the most important aspect for you?' were 'receiving complementary therapies on an individual or group basis' (26.2%); 'support and understanding received from therapists' (17.1%) and 'time spent with other patients at the centres' (16.1%). Positive (61.5%) and negative (38.5%) descriptions of 'other things affecting your health' correlated with larger and smaller improvement in concerns and well-being, respectively. CONCLUSIONS: In a multicentre evaluation, the MYCaW questionnaire provides rich data about patient experience, changes over time and perceptions of what was important to each individual with cancer within that experience. It is unlikely that meaningful evaluations of this complex intervention could be carried out by quantitative methods alone.

Outcome measures for holistic, complex interventions within the palliative care setting.

As members of the Association of Palliative Care CAM (complementary and alternative medicine) Task Group we set ourselves two tasks: the task of exploring different facets of holistic care relevant to the palliative care setting and then to review outcome measures that might assist in researching complex interventions such as complementary therapies. Complementary therapies often embrace holistic philosophy where mind and body are connected and the complexity of symptoms acknowledged. These holistic or complex interventions within the palliative care setting are important to research and research holistically. We therefore gathered together outcome measures in the areas of hope, spirituality, symptom control, self-concept, the therapeutic consultation and dignity which would assist in the design of clinical trials of complementary therapies in the palliative care setting.

Cyclic AMP signaling contributes to neural plasticity and hyperexcitability in AH sensory neurons following intestinal Trichinella spiralis-induced inflammation.

Trichinella spiralis infection causes hyperexcitability in enteric after-hyperpolarising (AH) sensory neurons that is mimicked by neural, immune or inflammatory mediators known to stimulate adenylyl cyclase (AC)/cyclic 3',5'-adenosine monophosphate (cAMP) signaling. The hypothesis was tested that ongoing modulation and sustained amplification in the AC/cAMP/phosphorylated cAMP related element binding protrein (pCREB) signaling pathway contributes to hyperexcitability and neuronal plasticity in gut sensory neurons after nematode infection. Electrophysiological, immunological, molecular biological or immunochemical studies were done in T. spiralis-infected guinea-pigs (8000 larvae or saline) after acute-inflammation (7 days) or 35 days p.i., after intestinal clearance. Acute-inflammation caused AH-cell hyperexcitability and elevated mucosal and neural tissue levels of myeloperoxidase, mast cell tryptase, prostaglandin E2, leukotrine B4, lipid peroxidation, nitric oxide and gelatinase; lower level inflammation persisted 35 days p.i. Acute exposure to blockers of AC, histamine, cyclooxygenase or leukotriene pathways suppressed AH-cell hyperexcitability in a reversible manner. Basal cAMP responses or those evoked by forskolin (FSK), Ro-20-1724, histamine or substance P in isolated myenteric ganglia were augmented after T. spiralis infection; up-regulation also occurred in AC expression and AC-immunoreactivity in calbindin (AH) neurons. The cAMP-dependent slow excitatory synaptic transmission-like responses to histamine (mast cell mediator) or substance P (neurotransmitter) acting via G-protein coupled receptors (GPCR) in AH neurons were augmented by up to 2.5-fold after T. spiralis infection. FSK, histamine, substance P or T. spiralis acute infection caused a 5- to 30-fold increase in cAMP-dependent nuclear CREB phosphorylation in isolated ganglia or calbindin (AH) neurons. AC and CREB phosphorylation remained elevated 35 days p.i.. Ongoing immune activation, AC up-regulation, enhanced phosphodiesterase IV activity and facilitation of the GPCR-AC/cAMP/pCREB signaling pathway contributes to T. spiralis-induced neuronal plasticity and AH-cell hyperexcitability. This may be relevant in gut nematode infections and inflammatory bowel diseases, and is a potential therapeutic target.

Autonomic nervous system and secretion across the intestinal mucosal surface.

Chloride secretion is important because it is the driving force for fluid movement into the intestinal lumen. The flow of accumulated fluid flushes out invading micro-organisms in defense of the host. Chloride secretion is regulated by neurons in the submucosal plexus of the enteric nervous system. Mechanosensitive enterochromaffin cells that release 5-hydroxytryptamine (5-HT) and activate intrinsic afferent neurons in the submucosal plexus and initiate chloride secretion. Mechanical stimulation by distention may also trigger reflexes by a direct action on intrinsic afferent neurons. Dysregulation of 5-HT release or altered activity of intrinsic afferents is likely to occur in states of inflammation and other disorders.

Measure Yourself Concerns and Wellbeing (MYCaW): an individualised questionnaire for evaluating outcome in cancer support care that includes complementary therapies.

BACKGROUND AND AIM: Descriptive and experimental evaluations of cancer support services require an outcome questionnaire that is valid, responsive to change, feasible and interpretable. This paper describes the development of such a tool. DEVELOPMENT OF THE QUESTIONNAIRE: A validated individualised measure MYMOP was adapted and piloted in two centres, and a multidisciplinary research team used this experience to develop the new questionnaire, Measure Yourself Concerns and Wellbeing (MYCaW). MYCaW requires participants to nominate one or two concerns and, using a seven-point scale, to score these concerns and their general feeling of wellbeing. The follow-up questionnaire also includes the open question 'Reflecting on your time with this Centre, what were the most important aspects for you?' INVESTIGATING VALIDITY: During 2003 the two centres administered MYCaW to all new patients, before and after a course of treatment. Patients nominated concerns that spanned physical, emotional and psychosocial concerns. For patients completing follow-up questionnaires (n=254 at the Cavendish Centre and n=267 at the Bristol Cancer Help Centre), the mean change (S.D.) for the first concern score was 2.9 (1.63) and 1.91 (1.58) for the second concern score 2.5 (1.73)/1.77 (1.96) and for the wellbeing score 1.4 (1.8)/0.61 (1.52), respectively. The open question collected valuable extra data. DISCUSSION: MYCaW is a questionnaire that is appropriate for the service offered, acceptable to patients, practitioners and researchers, and is responsive to change. Further validation work is planned.

ADOA3R as a therapeutic target in experimental colitis: proof by validated high-density oligonucleotide microarray analysis.

Adenosine A3 receptors (ADOA3Rs) are emerging as novel purinergic targets for treatment of inflammatory diseases. Our goal was to assess the protective effect of the ADOA3R agonist N(6)-(3-iodobenzyl)-adenosine-5-N-methyluronamide (IB-MECA) on gene dysregulation and injury in a rat chronic model of 2,4,6-trinitrobenzene sulfonic acid (TNBS)--induced colitis. It was necessary to develop and validate a microarray technique for testing the protective effects of purine-based drugs in experimental inflammatory bowel disease. High-density oligonucleotide microarray analysis of gene dysregulation was assessed in colons from normal, TNBS-treated (7 days), and oral IB-MECA-treated rats (1.5 mg/kg b.i.d.) using a rat RNU34 neural GeneChip of 724 genes and SYBR green polymerase chain reaction. Analysis included clinical evaluation, weight loss assessment, and electron paramagnetic resonance imaging/spin-trap monitoring of free radicals. Remarkable colitis-induced gene dysregulation occurs in the most exceptional cluster of 5.4% of the gene pool, revealing 2 modes of colitis-related dysregulation. Downregulation occurs in membrane transporter, mitogen-activated protein (MAP) kinase, and channel genes. Upregulation occurs in chemokine, cytokine/inflammatory, stress, growth factor, intracellular signaling, receptor, heat shock protein, retinoid metabolism, neural, remodeling, and redox-sensitive genes. Oral IB-MECA prevented dysregulation in 92% of these genes, histopathology, gut injury, and weight loss. IB-MECA or adenosine suppressed elevated free radicals in ex vivo inflamed gut. Oral IB-MECA blocked the colitis-induced upregulation (90% of genes tested (33 of 37 genes). We conclude that our validated high-density oligonucleotide microarray analysis is a powerful technique for molecular gene dysregulation studies to assess the beneficial effects of purine-based or other drugs in experimental colitis. ADOA3R is new potential therapeutic target for inflammatory bowel disease.

Mechanical stimulation releases nucleotides that activate P2Y1 receptors to trigger neural reflex chloride secretion in guinea pig distal colon.

Stroking the mucosal lining of the guinea pig colon with a brush elicits an intestinal neural reflex, and an increase in short-circuit current (Isc) indicative of chloride secretion. We tested whether endogenous and exogenous nucleotides are physiologic regulators of mucosal reflexes that modulate chloride secretion. The basal Isc was augmented by 6-N,N-diethyl-beta,gamma-dibromomethylene-D-adenosine-5'-triphosphate (ARL67156) inhibition of nucleotide breakdown or adenosine A1 receptor blockade and reduced by apyrase inactivation of nucleotidases, P2 receptor antagonists, tetrodotoxin (TTX), or piroxicam. ARL67156 augmented, and apyrase inhibited, stroking-evoked Isc responses. TTX and atropine inhibited nucleotide-evoked Isc responses. The agonist potency profile for Isc, 2-methylthioadenosine-diphosphate (2MeSADP) = 2-methioadenosine-triphosphate >> 5'adenosine-triphosphate (ATP) > or = 5'adenosine-diphosphate > 5'uridine-triphosphate > or = 5'uridine-diphosphate, supports a P2Y1 receptor (R). The P2 receptor antagonists suramin and pyridoxalphosphate-6-azophenyl-2'4'-disulfonic acid, reduced stroking responses (36%) and their effects were additive. The selective P2Y1 R antagonist, 2'deoxy-N6-methyl adenosine 3',5'-diphosphate diammonium salt, reduced stroking (54%) and 2MeSADP (70%) responses at P2Y1 Rs. The P2X1/3 R agonist, alpha,betaMeATP, increased Isc. A desensitizing dose of alpha,betaMeATP reduced stroking Isc responses but did not prevent the 2MeSADP-evoked Isc response. Reverse transcriptase polymerase chain reaction analysis revealed mRNAs for P2Y1 R, P2Y2 R, P2Y4 R, P2Y6 R, and P2Y12 R in submucosa. The expression of P2Y R immunoreactivity (ir) in cell bodies of submucous neurons followed the order of P2Y1 = P2Y2 >> P2Y4 R ir; P2Y1 Rs and P2Y2 R ir were abundant (21-50% of neurons). P2Y1 R ir was abundant in cholinergic secretomotor neurons and fewer than 2% of neuropeptide Y (NPY)/choline acetyltransferase secretomotor neurons, and P2Y2 R ir was expressed in virtually all NPY secretomotor neurons and approximately 30% of calbindin/intrinsic primary afferent neurons. P2Y4 R ir was present in NPY-positive neurons. P2Y ir was rare or absent in varicose nerve fibers. The functional data support the hypothesis that mechanical stimulation with a brush releases nucleotides that act predominantly at P2Y1 Rs and to a lesser extent on P2X1/3 Rs to mediate reflex chloride secretion. A separate P2Y2 R neural circuit pathway exists that is not activated by mechanical forces. Other receptors including P2Y4, P2Y6, P2Y12, or P4 Rs cannot be excluded.

Mechanically evoked reflex electrogenic chloride secretion in rat distal colon is triggered by endogenous nucleotides acting at P2Y1, P2Y2, and P2Y4 receptors.

Mechanical activation of the mucosal lining of the colon by brush stroking elicits an intestinal neural reflex and an increase in short circuit current (Isc) indicative of electrogenic chloride ion transport. We tested whether endogenous nucleotides are physiologic regulators of mucosal reflexes that control ion transport. The brush stroking-evoked Isc response in mucosa and submucosa preparations (M-SMP) of rat colon was reduced by the P2Y1 receptor (R) antagonist 2'deoxy-N6-methyl adenosine 3',5'-diphosphate diammonium salt (MRS 2179) and further blocked by tetrodotoxin (TTX). M-SMP Isc responses to serosal application of the P2Y1 R agonist 2-methylthioadenosine-diphosphate (2MeSADP) or the P2Y2/P2Y4 R agonist 5'uridine-triphosphate (UTP) were reduced but not abolished by TTX. The potency profile of nucleotides for increasing Isc was 5'adenosine-triphosphate (ATP; effective concentration at half maximal response [EC50] 0.65 x 10(4) M) congruent with UTP (EC50 1.0 x 10(-4) M) congruent with 2MeSADP (EC50 = 1.60 x 10(-4) M). Mucosal touch and distention-induced Ca2+ transients in submucous neurons were reduced by apyrase and prevented by blocking the P2Y1 R with MRS 2179 and TTX; denervation of the mucosa. It did not occur by touching a ganglion directly. 2MeSADP Ca2+ responses occurred in subsets of neurons with or without substance P (SP) responses. The potency profile of nucleotides on the neural Ca2+ response was 2MeSADP (5 x 10(-7) M) > UTP (6 x 10(-6) M) > ATP (9 x 10(-5) M). The expression of P2Y R immunoreactivity (ir) in nerve cell bodies was in the order of P2Y1 R > P2Y4 R >> P2Y2 R. P2Y1R ir occurred in the cell somas of more than 90% of neuronal nitric oxide synthase, vasoactive intestinal peptide (VIP), calretinin, or neuropeptide Y (NPY)-ir neurons, 78% of somatostatin neurons, but not in calbindin or SP neurons. P2Y2 R ir was expressed in a minority of SP, VIP, NPY, vesicular acetylcholine transporter, and calcitonin gene-related peptide-ir varicose fibers (5-20%) and those surrounding calbindin (5-20%) neurons. P2Y4 ir occurred mainly in the cell somas of 93% of NPY neurons. Reverse transcriptase polymerase chain reaction of the submucosa demonstrated mRNA for P2Y1R, P2Y2, P2Y4, P2Y6, and P2Y12 Rs. Expression of P2Y1, P2Y2, and P2Y4 protein was confirmed by western blots. In conclusion, endogenous nucleotides acting at P2YRs transduce mechanically evoked reflex chloride ion transport in rat distal colon. Nucleotides evoke reflexes by acting primarily at postsynaptic P2Y1 Rs and P2Y4 R on VIP+/NPY+ secretomotor neurons, at P2Y2 Rs on no more than 2% of VIP+ secretomotor neurons, and 2Y2 Rs mainly of extrinsic varicose fibers surrounding putative intrinsic primary afferent and secretomotor neurons. During mucosal mechanical reflexes, it is postulated that P2Y1 R, P2Y2 R, and P2Y4 R are activated by endogenous ATP, UTP, and 5'uridine-diphosphate.

Rabbit chronic ileitis leads to up-regulation of adenosine A1/A3 gene products, oxidative stress, and immune modulation.

A rabbit model of chronic ileitis has helped decipher the mechanism of alteration of multiple electrolyte and nutrient malabsorptions in inflammatory bowel disease (IBD). This study examined alterations in the adenosine A1/A3 receptor, oxidant, antioxidant, and immune-inflammatory pathways in chronic ileitis. Chronic ileal inflammation was induced 13-15 days after infection with 10,000 Eimeria magna oocytes. Quantitative analysis in 16 rabbits was done for oxidants, antioxidants, A1 and A3 transcripts, transport, injury, and inflammatory mediators. Inflamed gut had villus blunting, crypt hyperplasia and fusion, and immune cell infiltration. Alkaline phosphatase and Na-glucose co-transport were reduced by 78% (P=0.001) and 89% (P=0.001), respectively. Real-time fluorescence monitoring (TaqMan)-polymerase chain reaction revealed a transcriptional up-regulation of 1.34-fold for A1 and 5.40-fold for A3 receptors in inflamed gut. Lipid peroxidation increased in the mucosa (78%, P=0.012), longitudinal muscle-myenteric plexus (118%, P=0.042), and plasma (104%, P=0.001). Mucosal antioxidants were altered by inflammation: reductions occurred in superoxide dismutase (32%, P=0.001) and catalase (43%, P=0.001), whereas increases occurred in glutathione (75%, P=0.0271) and glutathione reductase (86%, P=0.0007). Oxidant enzyme activities were elevated by 21% for xanthine oxidase (P=0.004), 172% for chloramine (P=0.022), 47% for gelatinase (P=0.041), and 190% for myeloperoxidase (P=0.002). Mast cell tryptase increased by 79% (P=0.006). Increases occurred in the plasma concentration of leukotriene B(4) (13-fold, P=0.003), thromboxane B(2) (61-fold, P=0.018), and tumor necrosis factor-alpha (9-fold, P=0.002). In conclusion, chronic ileitis and tissue injury are associated with discrete alterations in complex multi-level oxidant, antioxidant, and immune inflammatory components. The rabbit ileitis model is a suitable model to gain further insight into chronic inflammation and IBD. We hypothesize that adenosine A3 and A1 receptors may provide a novel target for therapy in chronic ileitis and perhaps IBD.

A multi-tyrosinated sst1/2 receptor preferring somatostatin agonist inhibits reflex and immune-mediated secretion in the guinea pig colon.

Somatostatin and its analogs such as WOC 3B were compared for their ability to alter the release of 5-hydroxytryptamine (5-HT) and prostaglandins and to affect chloride secretory capacity, determined by activity of neural reflexes or by the influence of immune mediators and other secretagogues. In guinea pig colon set up in flux chambers, the multi-tyrosinated sst1/sst2 receptor preferring somatostatin agonist, WOC 3B, inhibited stroking-evoked 5-HT release without affecting basal release. WOC 3B had no effect on stroking-induced or basal prostaglandin E2 release (PGE2). Neither 5-HT nor PGE2 release was dependent on neural input. Tetrodotoxin induced a decrease in basal short circuit current (Isc) indicative of a decrease in chloride secretion. The decrease in basal Isc during neural blockade was highly correlated with the decrease in basal Isc when WOC 3B was used. In piroxicam- and atropine-treated tissues, to eliminate prostaglandins and cholinergic muscarinic input to crypts, WOC 3B further reduced the piroxicam-resistant and not the atropine resistant Isc during brush stroking the mucosa. Somatostatin and WOC 3B reduced the stroking-evoked Isc with similar half maximum concentrations of 1-2 nM. WOC 3B reduced by more than 50% dimaprit-evoked cyclical Isc. The rank order of potencies in inhibiting dimaprit-evoked Isc was: Somatostatin-14=WOC 3B>CH275=DC-32-92>DC-23-48>> >>DC-32-87=DC-32-97. Low nanomolar concentrations of WOC 3B primarily inhibited the neural effects of carbachol and forskolin on Isc without altering their epithelial effects. Equi-molar concentrations (4 nM) of CH275, a somatostatin sst1 receptor agonist, and the somatostatin sst2 receptor agonist, [Tyr(3)]-octreotide, inhibited dimaprit-evoked Isc by 25% and 26%, and their effects were additive. The results suggest that WOC 3B, a somatostatin analogue containing three tyrosine residues, has anti-secretory effects due to activation of somatostatin sst1 and sst2 receptors on enteric neurons.

Purinergic autocrine regulation of mechanosensitivity and serotonin release in a human EC model: ATP-gated P2X3 channels in EC are downregulated in ulcerative colitis.

BACKGROUND: Alterations in 5-hydroxytryptamine (HT) signaling in inflamed gut may contribute to pathogenesis of inflammatory bowel diseases. Adenosine 5'-triphosphate (ATP) regulates mucosal-mechanosensory reflexes and ATP receptors are sensitive to mucosal inflammation. Yet, it remains unknown whether ATP can modulate 5-HT signaling in enterochromaffin cells (EC). We tested the novel purinergic hypothesis that ATP is a critical autocrine regulator of EC mechanosensitivity and whether EC expression of ATP-gated P2X3-ion channels is altered in inflammatory bowel diseases. METHODS: Laser confocal (fluo-4) Ca imaging was performed in 1947 BON cells. Chemical stimulation or mechanical stimulation (MS) was used to study 5-HT or ATP release in human BON or surgical mucosal specimens, and purine receptors by reverse transcription-polymerase chain reaction, Western Blot, or P2X3-immunoreactivity in BON or 5-HT human EC (hEC) in 11 control and 10 severely inflamed ulcerative colitis (UC) cases. RESULTS: ATP or MS triggered Ca-transients or 5-HT release in BON. ATP or adenosine diphosphate increased 5-HT release 5-fold. MS caused ATP release, detected after 5'ecto-ATPase inhibition by ARL67156. ARL67156 augmented and apyrase blocked Ca/5-HT mechanosensitive responses. 2-Methyl-thio-adenosine diphosphate 5'-monophosphate-evoked (P2Y1,12) or mechanically-evoked responses were blocked or augmented by a P2Y1,12 antagonist, MRS2179, in different cells or inhibited by U73122. A P2Y12 antagonist, 2MeSAMP, augmented responses. A P2X1,3 agonist, α,ß-MeATP, triggered Ca responses, whereas a P2X1,2/3,3 antagonist, 2',3'-O-(2,4,6-trinitrophenyl)-ATP, blocked mechanical responses or cell-surface 5'ATP- labeling. In hEC, α,ß-MeATP stimulated 5-HT release. In UC, P2X3-immunoreactivity decreased from 15% to 0.2% of 5-HThECs. Human mucosa and BON expressed P2X1, P2X3, P2X4, P2X5, P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, and P2Y12R-messenger RNA transcripts. CONCLUSIONS: ATP is a critical determinant of mechanosensation and 5-HT release via autocrine activation of slow P2Y1-phospholipase C/inositol-1,4,5-triphosphate-Ca or inhibitory P2Y12-purinergic pathways, and fast ATP-gated P2X3-channels. UC downregulation of P2X3-channels (or A2B) is postulated to mediate abnormal 5-HT signaling.