AGA Abstracts (mean±SD: 86±12 and 91±10 vs. 100±8 mmHg, p=0.007 and p=0.013, resp.). Five CD and 5 UC patients had pathological results (rise in diastolic blood pressure during the SHGT < 10 mmHg). Compared with healthy controls, mean 30:15 ratio tended to be decreased in UC patients, only (1.07±0.16 vs. 1.21±0.19, p=0.07). Three CD patients and 6 UC patients had pathological results (30:15 ratio < 1.03). Two CD and 3 UC patients showed affection of both, sympathetic and parasympathetic function. Neither sympathetic nor parasympathetic dysfunction was associated with gastric emptying parameters in any of the groups or with disease activity in IBD patients. Conclusions: Using clinically available tests, we observed signs of autonomic dysfunction including sympathetic and/or parasympathetic neuropathy in a substantial subset of patients with CD and UC. Autonomic neuropathy was not associated with and, thus, probably had no major influence on, gastric emptying. T2063 Inflammatory and Hematologic Disorders are Associated With GI Symptoms in Diabetic Gastroparesis Shabnam Sarker, Naveed Ahmad, Archana Kedar, Danielle C. Spree, Michael Griswold, Christopher J. Lahr, Thomas L. Abell, William A. Rock, Gailen D. Marshall INTRODUCTION: Inflammation (assessed via BMI and CRP measures), autoimmunity and coagulopathy are associated by an unknown mechanism with gastroparesis (GP) of diabetic (DM) etiology, and may exacerbate symptom severity. Here we compared CRP, BMI, inflam- mation, and hypercoagulability values for patients with DM GP. PATIENTS: 143 patients with DM and GP symptoms (103 f, 38 m; mean age 48.7 yrs) rated vomiting, nausea, bloating-distention, anorexia-early satiety, and abdominal pain on five Likert scale tools (0= no, 4=most severe). Patient BMI, inflammation, and coagulation measures were also obtained. Idiopathic GP (ID GP) patients were used as controls (224 f, 40 m; mean age 43.5 yrs) METHODS: All ratings were summed for a Total Symptom Score (TSS: 0-20). Inflammation was evaluated by CRP (normal range 0.0-0.9 mg/dl). Coagulation, assessed by fibrinogen (normal 150-400 mg/dl) and Factor VII and VIII assays (normals 50-150%) and BMI (normal ÿ15.6 to <25) were compared with TSS by using descriptive statistics, as well as Pearson and Spearman correlation co-efficients. RESULTS: Mean symptom scores were: nausea, 3.4; vomiting, 2.6; abdominal pain, 3.0; early satiety, 3.0; and bloating, 2.9. Mean scores for TSS (14.9) and elevated group CRP (6.99) were also obtained. Linear regression correlations between variables are noted in Table 1. CRP and DM status differ between DM GP and ID GP regardless of BMI. CONCLUSION: GP DM is often accompanied by inflammation, coagulation, and increased symptom severity. These findings imply that mechanisms may exist relating inflammatory and hematologic factors occur in diabetic gastroparesis. T2064 Altered Serotonin Signaling and Extrinsic Sensory Neuron Activation in Irritable Bowel Syndrome Cesare Cremon, Giovanni Carini, Giovanni Dothel, Valentina Vasina, Roberto De Giorgio, Vincenzo Stanghellini, Fabrizio De Ponti, Marcello Tonini, David Grundy, Roberto Corinaldesi, Giovanni Barbara Background & Aims: Serotonin (5-hydroxytryptamine, 5-HT) metabolism is altered in some gut disorders including the irritable bowel syndrome (IBS). The aims of the present study were to: 1) evaluate colonic 5-HT-positive EC cells in IBS in comparison with healthy controls (HC); 2) determine the amount of 5-HT released from the colonic mucosa of patients with IBS and HC; and 3) test the effects of mucosal 5-HT released from the colonic mucosa of IBS patients on electrophysiological responses from rat mesenteric sensory nerve fibers supplying the gut In Vitro. Methods: Mucosal biopsies were obtained from the des- cending colon of 24 IBS patients and 12 HC. 5-HT-positive EC cell were identified immunohi- stochemically and quantified with a computer assisted method. Mucosal 5-HT was collected from biopsies and quantification was assessed using reverse-phase, ion-pair, high-perform- ance liquid chromatography coupled with electrochemical detection. The impact of mucosal 5-HT on electrophysiological activity of rat mesenteric afferent nerves was evaluated In Vitro. Results: Overall, IBS patients showed a significant increase in the area of crypt epithelium occupied by 5-HT-positive cells compared to HC. This feature was significantly greater in diarrhea-predominant IBS compared to constipation-predominant IBS (P = 0.03; one-way ANOVA). 5-HT release in IBS patients was significantly increased by 10-fold over the release found in HC. This spontaneous release was not different in diarrhea and constipation predominant subgroups. Average peak responses obtained with IBS supernatants were signi- ficantly increased by 5 fold over that obtained with HC samples. The 5-HT3 antagonist granisetron did not affect neuronal peak responses obtained by IBS sample. However, the area under the curve obtained with granisetron-treatment was significantly reduced with respect to that obtained with IBS samples (3636.15 ± 1396.38 vs. 1133.60 ± 1634.91, P = 0.031 one-way ANOVA). Conclusions: An increased amount of 5-HT is released in the colonic mucosa of IBS patients and can signal to sensory nerves. Our results provide novel insight into the mechanism underlying visceral hypersensitivity in IBS and open new perspectives in the treatment of IBS patients. S-624 AGA Abstracts T2065 Molecular Characterization of the Fecal and Mucosal-Associated Intestinal Microbiota in Patients With Diarrhea-Predominant IBS and Healthy Subjects Ian M. Carroll, Temitope O. Keku, Tamar Ringel-Kulka, R. Balfour Sartor, Yehuda Ringel Recent studies have suggested a role for an altered intestinal microbiota in the pathophysiology of irritable bowel syndrome (IBS). Studies in healthy individuals have shown that the microbiota associated with the intestinal mucosa differs from the microbiota in the intestinal lumen. However, there is no data regarding the differences between these two niches in IBS. Aim: To investigate the luminal and mucosal-associated intestinal microbiota in patients with diarrhea-predominant IBS (D-IBS). Methods: We analyzed fecal samples from 30 patients who met the Rome III criteria for D-IBS and 16 healthy controls (HC). In 20 subjects (10 from D-IBS and 10 from HC) intestinal biopsies were also collected during an un-prepped flexible sigmoidoscopy. DNA was extracted from all samples and the microbiota was charac- terized by terminal-restriction fragment length polymorphism (T-RFLP)-PCR of 16S rRNA genes. The composition and diversity of T-RFLP fingerprints (that represent the different bacterial species within a complex microbial environment) were compared between groups using hierarchal clustering and principal component analysis (Primer6™). Results: I. Com- position of T-RFLP fingerprints: Mucosal samples from D-IBS patients showed a composi- tional difference in T-RFLP fingerprints compared to HC (R = 0.163, P = 0.07). Conversely, the composition of the T-RFLP fingerprints in the fecal samples were not significantly different between the two groups (R = 0.049, P = 0.19). Significant differences in the composition of T-RFLP fingerprints between fecal and mucosal samples were detected in both D-IBS patients (R = 0.132, P = 0.039) and HC (R = 0.781, P = 0.002). II. Diversity of T-RFLP fingerprints: A significant increase in the diversity of T-RFLP fingerprints from mucosal samples was found in D-IBS patients when compared to HC (2.4 vs. 1.6, P = 0.04), however no significant differences in diversity were detected between groups in fecal samples. In addition, a significant difference in diversity between fecal and mucosal samples was found in samples from HC (1.6 vs. 2.7, P =0.008) while no such differences were detected in D-IBS samples. Conclusions: Our data suggests that the microbiota associated with the intestinal mucosa may have a greater role than the fecal microbiota in the pathophysiology of D-IBS. Additionally, our data demonstrate that the distinction in composition and diversity between the mucosal associated and fecal microbiota is lower in D-IBS patients, further suggesting a dysbiosis within the intestinal tract of D-IBS patients. Analysis of the mucosal- associated microbiota in un-prepped biopsies may be more informative than fecal samples. T2066 Klotho-Beta Gene Polymorphism is Associated With Colonic Transit in Health and Lower Functional Gastrointestinal Disorders Banny S. Wong, Michael Camilleri, Paula Carlson, Duane D. Burton, Sanna McKinzie, Noriaki Manabe, Archana S. Rao, Alan R. Zinsmeister BACKGROUND & AIM: Klotho-beta (KLb) is a transmembrane protein expressed by hepatocytes involved in FGF19-mediated negative regulation of bile acid (BA) synthesis. KLb-/- mice show elevated BA synthesis and excretion. BA malabsorption was reported in 20-50% patients with functional diarrhea (FD) or IBS with diarrhea (IBS-D). AIM: To determine association of single nucleotide polymorphisms (SNPs) in the KLb gene and 6 other genes involved in BA metabolism (ASBT, FGFR4, OST-alpha, OST-beta, SHP, and CYP7A1) with symptom phenotypes and GI functions in health and functional GI disorders (FGID). METHODS: 15 non-synonymous or tag SNPs in the coding sequences of candidate genes were chosen for genotyping based on minimum minor allele frequency of >9%. Genotyping was performed in 465 FGID patients (IBS-D, IBS-constipation [IBS-C], and IBS- mixed [IBS-M]) and 231 healthy controls. Associations between genotype variants and GI and colonic physiology (including gastric emptying and accommodation, small bowel and colonic transit, and rectal compliance and sensation by validated methods) were examined using ANCOVA models adjusting for gender, clinical subgroup, and BMI. A false discovery rate (FDR) method was used to adjust for the multiple genotypes studied in assessing overall statistical significance. RESULTS: Demographics for those who underwent colonic transit (N=172) are shown in the table. There was a significant association of SNP rs17618244 in the KLb gene with colonic transit at 24 and 48 hours. Using a dominant genetic model, the minor A allele of SNP rs17618244, compared to the major G allele, was associated with delayed colonic transit (GC24=2.50±0.18 [GA/AA] vs 2.99±0.15 [GG], p=0.0033 [FDR- adjusted p<0.05]; GC48=3.55±0.18 [GA/AA] vs 4.08±0.15 [GG], p=0.0018 [FDR-adjusted p<0.05]). This delayed colonic transit was seen in each subgroup (healthy, IBS-C, IBS-D, and IBS-M) in the cohort, but was most notable in the healthy (GC24=2.15±0.40 [GA/AA] vs 3.02±0.25 [GG]) and IBS-D subgroups (GC24=2.98±0.20 [GA/AA] vs 3.53±0.15 [GG]). No other significant associations were found between SNPs and symptom phenotypes or GI functions after FDR correction. CONCLUSIONS: KLb variants are associated with colonic transit in health and FGID. The role of KLb gene polymorphisms in colonic transit and susceptibility to disorders of colonic motility and chronic diarrhea associated with BA malabsorption deserves further study.