The link between negative affect,vagal tone,and visceral sensitivity in quiescent Crohn's disease

Autonomic dysfunction and mood disorders are frequently described in Crohn's disease (CD) and are known to influence visceral sensitivity. We addressed the link between vagal tone, negative affect, and visceral sensitivity in CD patients without concomitant features of irritable bowel syndrome (IBS). Rectal distensions to a discomfort threshold of 70% and onset of pain were performed in nine CD patients in remission and eight healthy controls. Autonomic parameters were evaluated with heart rate variability and electrodermal reactivity. We showed that CD patients had (i) higher scores of depressive symptomatology (12 ± 3 in patients vs 4 ± 1 in controls on the Center for Epidemiologic Studies‐Depression Scale; p = 0.038), (ii) reduced vagal tone (HF 257 ± 84 ms² vs 1607 ± 1032 ms², p = 0.043; LF 455 ± 153 ms² vs 1629 ± 585 ms², p = 0.047), (iii) decreased sympathetic reactivity during an aversive stimulus, and (iv) higher tolerance to rectal distension pressures (43 ± 3 mmHg vs 30 ± 2 mmHg, p = 0.002) and low sensitivity index scores. In conclusion, our results provide preliminary evidence that patients with quiescent CD, in the absence of IBS, are hyposensate to experimental rectal distension. These data provide further evidence that anxiety and depressive symptomatology in addition to autonomic dysfunction modulate visceral pain perception in quiescent CD patients in the absence of IBS.     

Vagal tone: effects on sensitivity,motility, and inflammation

The vagus nerve (VN) is a key element of the autonomic nervous system. As a mixed nerve, the VN contributes to the bidirectional interactions between the brain and the gut, i.e., the brain‐gut axis. In particular, after integration in the central autonomic network of peripheral sensations such as inflammation and pain via vagal and spinal afferents, an efferent response through modulation of preganglionic parasympathetic neurons of the dorsal motor nucleus of the vagus and/or preganglionic sympathetic neurons of the spinal cord is able to modulate gastrointestinal nociception, motility, and inflammation. A low vagal tone, as assessed by heart rate variability, a marker of the sympatho‐vagal balance, is observed in functional digestive disorders and inflammatory bowel diseases. To restore a normal vagal tone appears as a goal in such diseases. Among the therapeutic tools, such as drugs targeting the cholinergic system and/or complementary medicine (hypnosis, meditation…), deep breathing, physical exercise, VN stimulation (VNS), either invasive or non‐invasive, appears as innovative. There is new evidence in the current issue of this Journal supporting the role of VNS in the modulation of gastrointestinal functions.     

Characterization of sensations induced by capsaicin in the upper gastrointestinal tract

Intraluminal capsaicin induces perception in the jejunum, but chemosensitivity of proximal gastrointestinal regions is unclear. Our aim was to evaluate the quality of perception induced by intraluminal capsaicin in different regions of the upper gastrointestinal tract. Healthy volunteers received either an oral tube for distension and capsaicin perfusion of the mid-duodenum or jejunum or swallowed a capsule containing 0.75 mg capsaicin powder. Graded questionnaires evaluated quality and severity of sensations during distensions, capsaicin infusion and 30 min after ingestion of capsaicin capsules respectively. Duodenal capsaicin induced sensations at lower doses than jejunal capsaicin (P < 0.05). Most prominent sensations evoked by capsaicin infusion were pressure, cramps, pain and nausea; nausea and warmth were more intense during capsaicin infusion than distension (P < 0.05,for the duodenum and jejunum), pain was more intense during distension (P < 0.05, duodenum only). Gastric ingestion of capsaicin capsules mainly induced sensations of pressure, heartburn and warmth. Capsaicin application into the upper gastrointestinal tract reproducibly induced upper abdominal sensation. Qualitative features distinguished chemically from mechanically induced sensations, but both sensitivity for chemical and mechanical stimulation decreased along the intestine. Activation of chemical pathways could be a useful human pain model activating nociceptors apart from mechanical stimulation.     

Contribution of genoarchitecture to understanding forebrain evolution and development, with particular emphasis on the amygdala

The amygdala is a forebrain center involved in functions and behaviors that are critical for survival (such as control of the neuroendocrine system and homeostasis, and reproduction and fear/escape responses) and in cognitive functions such as attention and emotional learning. In mammals, the amygdala is highly complex, with multiple subdivisions, neuronal subtypes, and connections, making it very difficult to understand its functional organization and evolutionary origin. Since evolution is the consequence of changes that occurred in development, herein we review developmental data based on genoarchitecture and fate mapping in mammals (in the mouse model) and other vertebrates in order to identify its basic components and embryonic origin in different species and understand how they changed in evolution. In all tetrapods studied, the amygdala includes at least 4 components: (1) a ventral pallial part, characterized by expression of Lhx2 and Lhx9, that includes part of the basal amygdalar complex in mammals and a caudal part of the dorsal ventricular ridge in sauropsids and also produces a cell subpopulation of the medial amygdala; (2) a striatal part, characterized by expression of Pax6 and/or Islet1, which includes the central amygdala in different species; (3) a pallidal part, characterized by expression of Nkx2.1 and, in amniotes, Lhx6, which includes part of the medial amygdala, and (4) a hypothalamic part (derived from the supraoptoparaventricular domain or SPV), characterized by Otp and/or Lhx5 expression, which produces an important subpopulation of cells of the medial extended amygdala (medial amygdala and/or medial bed nucleus of the stria terminalis). Importantly, the size of the SPV domain increases upon reduction or lack of Nkx2.1 function in the hypothalamus. It appears that Nkx2.1 expression was downregulated in the alar hypothalamus during evolution to mammals, which may have produced an enlargement of SPV and the amygdalar cell subpopulation derived from it.     

Neurochemical coding in the myenteric plexus of the upper gastrointestinal tract of hibernating hamsters

As part of our investigation of the plasticity of autonomic nerves in physiological and pathological conditions, we have examined the effect of hibernation on the neurochemical content of myenteric nerves and nerve cell bodies of the upper gastrointestinal tract of the non-seasonal hibernator, the golden hamster. Age matched hamsters kept at room temperature and those kept at 5°C but failed to hibernate, were used as controls. Possible changes in nerve fibers and nerve cell bodies containing the general neuronal marker, protein gene product 9.5, the peptides, vasoactive intestinal polypeptide, substance P (SP) and calcitonin gene-related peptide (CGRP), the catecholamine synthesizing enzyme tyrosine hydroxylase and the enzyme responsible for synthesizing nitric oxide, nitric oxide synthase, were examined in the oesophagus, proventriculus and proximal and distal stomach of the golden hamsters using immunohistochemical techniques. The results of the present study revealed a significant increase in the number of nerve cell bodies and density of nerve fibers containing SP-immunoreactivity and increased number of CGRP-immunoreactive cell bodies but not the other markers examined in the proximal stomach and proventriculus. In contrast, there was no change in the distribution of any of the neuroactive substances examined in the myenteric plexus of the oesophagus and distal stomach. It is suggested that the change in the environment of the hibernating hamsters perturbs the normal digestive physiology in the proximal stomach and proventriculus that is reflected by the selective changes in SP- and CGRP-containing enteric nerves; these changes may be part of protective reflex mechanisms to the environmental changes resulting from hibernation, where upgrading of nerve cell bodies expessing CGRP and SP has occurred.     

Influence of age on rectal tone and sensitivity to distension in healthy subjects

Hypersensitivity to rectal distension is frequently observed in patients with irritable bowel syndrome (IBS). However, few data are available about the influence of age on rectal sensory thresholds and tone. The aim of this study was to measure rectal sensory thresholds and tone with a barostat in 12 healthy subjects (aged 86 +/- 4 years, eight females, four males) as compared with 12 young healthy male controls (26 +/- 1 years). Isobaric phasic distensions were performed in the fasted state (increment of 4 mmHg, steps of 5 min, interval of 5 min). Rectal tone changes were then measured as changes in volume of the barostat bag, the pressure being kept constant. After a baseline recording of 1 h, a 1000-kcal meal was served and the tone recorded until return to baseline. Rectal sensory thresholds were significantly higher in aged subjects. First sensation, sensation of urge to defaecate and sensation of pain were triggered at 21.1 +/- 3.2 mmHg, 30.4 +/- 5.4 mmHg and 40.5 +/- 5.0 mmHg, respectively, in aged subjects, vs 13.3 +/- 4.6 mmHg (P < 0.05), 20.7 +/- 1.0 mmHg (P < 0.001) 31.3 +/- 1.7 mmHg (P < 0.001) in controls. Rectal compliance was not significantly different between the two groups. Mean barostat bag volume was 104 +/- 13 mL in fasting aged subjects and 125 +/- 23 mL in controls (NS). After the meal, the barostat bag volume decreased by 69 +/- 11% during 85 +/- 17 min in aged subjects and 75 +/- 14% during 89 +/- 15 min in young controls (NS). Rectal sensory thresholds triggered by distension are increased in aged healthy subjects while compliance and tone are not different. Age should be considered as a confounding factor when studying rectal sensitivity and further studies in aged patients with IBS should include a group of control subjects within the same range of age as studied patients.     

Effect of DSS-induced colitis on visceral sensitivity to colorectal distension in mice

The present study aimed at evaluating the effect of dextran sodium sulphate (DSS)-induced colitis on visceral sensitivity, measured as the visceromotor response (VMR) to colorectal distension (CRD) in BALB/c and C57Bl/6 male mice. Inflammation was induced by the addition of 4% DSS to the drinking water for 5 (C57Bl/6) or 6-7 days (BALB/c). Parallel groups were used to monitor histopathological changes and visceral sensitivity. Pseudo-affective visceral pain responses were evoked using an increasing phasic CRD paradigm (10-60 mmHg) in conscious mice on predetermined days (pretreatment controls, 12, 16, 20, 30, 40 and 51). In both mouse strains, significant histopathological changes developed between days 2 and 5 of DSS treatment, and persisted until day 12 (P < 0.05). On day 15, inflammatory scores were reduced by about 50%. Despite evidence of inflammation in DSS-treated mice, no differences could be shown in the VMR to CRD between DSS-treated mice and controls at any time point tested. In addition, no differences were seen before and after DSS treatment in the same group of mice. In conclusion, these data suggest that DSS-induced colonic inflammation does not affect the visceral sensitivity to CRD, neither at short or long term, in BALB/c or C57Bl/6 male mice.     

Cerebral slow waves related to the perception of pain in man

Significant amplitude and temporal augmentation occurred in later time segments of human somatosensory evoked responses (60–700 ms) when percutaneous electrical pulse stimulation, delivered to finger, toe, or lip, indicated subjectively both crossing of a perceptual pain threshold and somatotopic movement associated with a noxious, qualitative change. Sequential pseudorandomizing of stimulus intensity (noxious and nonnoxious) or modality (contingent acoustic clicks) suggested that the waveform changes represented, at least in part, stimulus-specific information due to differential activation of peripheral fiber systems, rather than stimulus-nonspecific processing of event significances. The late waves were localizable, on scalp, to parietal and vertex regions, with insignificant contralateralization for finger stimuli. Their augmentation was related to subjective reports rather than to physical stimulus parameters, confirming previous data on potentially noxious mechanical stimulation of digits and palm, and another laboratory's noxious stimulation of tooth pulp. Subsequent data from a third laboratory, resulting from noxious laser stimulation of forearm, have replicated this late, slow-wave activity.     

Neural plasticity in the gastrointestinal tract: chronic inflammation, neurotrophic signals, and hypersensitivity

Neural plasticity is not only the adaptive response of the central nervous system to learning, structural damage or sensory deprivation, but also an increasingly recognized common feature of the gastrointestinal (GI) nervous system during pathological states. Indeed, nearly all chronic GI disorders exhibit a disease-stage-dependent, structural and functional neuroplasticity. At structural level, GI neuroplasticity usually comprises local tissue hyperinnervation (neural sprouting, neural, and ganglionic hypertrophy) next to hypoinnervated areas, a switch in the neurochemical (neurotransmitter/neuropeptide) code toward preferential expression of neuropeptides which are frequently present in nociceptive neurons (e.g., substance P/SP, calcitonin-gene-related-peptide/CGRP) and of ion channels (TRPV1, TRPA1, PAR2), and concomitant activation of peripheral neural glia. The functional counterpart of these structural alterations is altered neuronal electric activity, leading to organ dysfunction (e.g., impaired motility and secretion), together with reduced sensory thresholds, resulting in hypersensitivity and pain. The present review underlines that neural plasticity in all GI organs, starting from esophagus, stomach, small and large intestine to liver, gallbladder, and pancreas, actually exhibits common phenotypes and mechanisms. Careful appraisal of these GI neuroplastic alterations reveals that—no matter which etiology, i.e., inflammatory, infectious, neoplastic/malignant, or degenerative—neural plasticity in the GI tract primarily occurs in the presence of chronic tissue- and neuro-inflammation. It seems that studying the abundant trophic and activating signals which are generated during this neuro-immune-crosstalk represents the key to understand the remarkable neuroplasticity of the GI tract.     

Relative sensitivity to alfentanil and reliability of current perception threshold vs von Frey tactile stimulation and thermal sensory testing

Recent technological advances claim to allow quantitative measurement of the functional integrity of both large and small diameter sensory nerve fibers using the current perception threshold (CPT) sensory testing device. This device has yet to be validated against the corresponding gold standard references for sensory testing (thermal sensory testing [TST]) and von Frey tactile hair stimulation [VF]) to correlate its evaluation of similar sensory nerve perceptions. A baseline neurosensory examination using the CPT, TST and VF methods was performed on 19 healthy volunteers. Using a randomized, double-blind, placebo-controlled design, each subject received an alfentanil or diphenhydramine (as a placebo control) infusion in separate study sessions. The order of the study sessions was randomized and separated by 1 week. The 3 neurosensory examinations were repeated at 3 different targeted plasma levels of study drug. Changes in neurosensory thresholds were then compared between the 3 methods. All CPT measurements and the cold pain measurement showed a significantly higher degree of variability than the other TST and VF measurements. There appeared to be a correlation between the CPT 5 Hz pain threshold and the TST cold pain and warm sensation; intravenous alfentanil significantly elevated all 3 detection thresholds. In addition, there was no effect of alfentanil on the VF or the CPT 2000 Hz thresholds. However, we did not see the predicted relation between the 250 Hz CPT stimulus and cool sensation. From these studies, there is some evidence that similar fiber tracts may be measured between the CPT, TST, and VF methods, especially with the CPT 5 Hz measures and C-fiber tract activity.     

Association of upper and lower gastrointestinal tract symptoms with body mass index in an Australian cohort

Food modulates gastrointestinal (GI) function and GI symptoms could alter food intake, but it is not established whether or not obese people experience more or less GI symptoms. We aimed at evaluating the association between body mass index (BMI) and specific GI symptoms in the community. Population-based random samples from Sydney, Australia (n = 777) completed a validated questionnaire. The association of each GI symptom with BMI (kg m(-2)) categories was assessed using logistic regression analysis adjusting for potential confounders. The prevalence of obesity (BMI > or =30 kg m(-2)) was 22%. There were univariate associations (adjusting for age, sex, education level, alcohol and smoking) between increased BMI category and heartburn (OR = 1.9, 95% CI 1.4, 2.5), acid regurgitation (OR = 2.1, 95% CI 1.4, 2.9), increased bloating (OR = 1.3, 95%CI 1.1, 1.6), increased stool frequency (OR = 1.4, 95% CI 1.1, 1.7), loose and watery stools (OR = 1.5, 95% CI 1.1, 2.0) and upper abdominal pain (OR = 1.3, 95% CI 1.03, 1.6). Early satiety was associated with a lower BMI category but this was not significant after adjustment (OR = 0.8, 95% CI 0.6, 1.1). Lower abdominal pain, postprandial fullness, nausea and vomiting were not associated with BMI category. In a regression model adjusting for sex, education, smoking, alcohol and all GI symptoms, older age, less early satiety and increased stool frequency and heartburn were all independently associated with increasing BMI (all P < 0.01). Heartburn and diarrhoea were associated with increased BMI, while early satiety was associated with a lower BMI in this population.     

Rectal visceral sensitivity in healthy volunteers: influences of gender, age and methods.

The barostat is a device that maintains a constant pressure within an air-filled polyethylene bag by means of a feedback mechanism. The system measures variations in rectal tone by recording changes in the intrarectal pressure and volume. Different procedures, such as ramp distension or intermittent distension, are used to test visceral sensitivity and rectal wall compliance. It is not quite clear which method is preferable and how the barostat measurements compare with those of the conventional latex balloon. In 28 healthy volunteers (11 males, mean age 36, range 22-67 years) rectal distension was performed in two ways: 1 Pressure-controlled distension, by both intermittent and ramp methods, with measurement on the Visual Analogue Scale (VAS, 0-5) at 8, 12, 16, 20, 24, 28, 32 and 36 mmHg. Hysteresis (comparing area under the curve during deflation and inflation with ramp pressure distension) and compliance were calculated. 2 Volume-controlled distension, with registration of first sensation, urge to defecate and maximal tolerated distension. This procedure was compared to conventional water-filled latex balloon distension. No differences were found between intermittent and ramp distension comparing VAS scores at the same pressures. Gender or age did not affect the VAS score. Males had larger volumes at the same pressures than females. Females had larger hysteresis than males. Older females had larger hysteresis than younger females. The pressure volume curves were S-shaped. Compliance at maximal tolerated distension (V/p) and maximal dynamic compliance (Delta V/Delta p) was higher in males than females. The polyethylene bag had higher MTV and MTP compared to the latex balloon. In conclusion, no differences were found in volumes, compliance or VAS between the intermittent and the ramp pressure-controlled inflation, indicating potential for simplification of the procedure. Males had larger rectal volumes and compliances; females had more pronounced hysteresis. A systemic difference was found between distension with the water-filled latex balloon and with the air-filled polyethylene bag. This should be taken into account when interpreting results.     

Compliance, tone and sensitivity of the rectum in different subtypes of irritable bowel syndrome

Irritable bowel syndrome (IBS) consists of various subtypes. It is not known whether these subtypes share a common pathophysiology. Evaluation of motor and sensory function of the rectum using a barostat may help to explore a common pathophysiological background or differences in pathophysiology in subtypes of IBS. We have evaluated compliance, tone and sensitivity of the rectum, in both fasting state and postprandially, using a computerized barostat in 15 patients with diarrhoea-predominant IBS (IBS-D), 14 patients with constipation-predominant IBS (IBS-C) and compared the results with those obtained in 12 healthy controls. Rectal compliance as calculated over the steep part of the pressure-volume curve (17-23 mmHg) was decreased in both IBS groups (IBS-D 8.0 +/- 1.4 mL mmHg-1; IBS-C 5.6 +/- 1.1 mL mmHg-1) compared with controls (24.7 +/- 3.5 mL mmHg-1). The perception of urge was increased only in IBS-D patients, whereas pain perception was significantly increased in both IBS groups. Spontaneous adaptive relaxation was decreased in IBS-D patients. Postprandially, rectal volume decreased significantly in the controls and in IBS-D patients, but not in IBS-C patients. In conclusion, both rectal motor and sensory characteristics are different between IBS-D and IBS-C patients. Therefore, testing of rectal visceroperception, adaptive relaxation and the rectal response to a meal may help distinguish groups of patients with different subtypes of irritable bowel syndrome.     

Contribution of joint and cutaneous afferents to longer-latency reflexes in man

Electromyographic records from wrist extensors and flexors show a short latency reflex response, M1 and a longer latency response comprising of M2 and M3 peaks. M1 corresponds to the spinal stretch reflex and hence mediated by spindle afferents. In order to determine the contribution of various afferent types to M2-M3 components and simple reaction times, reflexes were elicited before and after anaesthetic blocks of palm cutaneous and wrist joint afferents in human subjects. The results show that joint and cutaneous afferents have no significant contribution to the longer latency reflexes or simple reaction times.     

Contribution of the corticospinal tract to motor impairment in spina bifida

We aimed to disentangle the proportional contributions of upper and lower motor neuron dysfunction to motor impairment in children with spina bifida. We enrolled 42 children (mean age, 11.2 years; standard deviation, 2.8 years) with spina bifida and 36 control children (mean age, 11.4 years; standard deviation, 2.6 years). Motor impairment was graded to severity scales in children with spina bifida. We recorded motor evoked potentials after transcranial and lumbosacral magnetic stimulation and compound muscle action potentials after electric nerve stimulation. Regarding lower motor neuron function, severely impaired children with spina bifida demonstrated smaller compound muscle action potential areas and lumbosacral motor evoked potential areas than control children; mildly impaired children hardly differed from control children. Compound muscle action potential latencies and lumbosacral motor evoked potential latencies did not differ between children with spina bifida and control children. Regarding upper motor neuron function, children with spina bifida demonstrated smaller transcranial motor evoked potential areas and longer central motor conduction times than control children. The smallest motor evoked potential areas and longest central motor conduction times were observed in severely impaired children. In children with spina bifida, the contribution of upper motor neuron dysfunction to motor impairment is more considerable than expected from clinical neurologic examination.     

Contribution of the motor system to the perception of reachable space: an fMRI study

The present functional magnetic resonance imaging (fMRI) study investigates the neural correlates of reachability judgements. In a block design experiment, 14 healthy participants judged whether a visual target presented at different distances in a virtual environment display was reachable or not with the right hand. In two control tasks, they judged the colour or the relative position of the visual target according to flankers. Contrasting the activations registered in the reachability judgement task and in the control tasks, we found activations in the frontal structures, and in the bilateral inferior and superior parietal lobe, including the precuneus, and the bilateral cerebellum. This fronto‐parietal network including the cerebellum overlaps with the brain network usually activated during actual motor production and motor imagery. In a following event‐related design experiment, we contrasted brain activations when targets were rated as ‘reachable’ with those when they were rated as ‘unreachable’. We found activations in the left premotor cortex, the bilateral frontal structures, and the left middle temporal gyrus. At a lower threshold, we also found activations in the left motor cortex, and in the bilateral cerebellum. Given that reaction time increased with target distance in reachable space, we performed a subsequent parametric analysis that revealed a related increase of activity in the fronto‐parietal network including the cerebellum. Unreachable targets did not show similar activation, and particularly in regions associated to motor production and motor imagery. Taken together, these results suggest that dynamical motor representations used to determine what is reachable are also part of the perceptual process leading to the distinct representation of peripersonal and extrapersonal spaces.     

Disorders of the gastrointestinal tract in children: consultation-liaison experience

Disorders of the gastrointestinal tract are common in children. Fortunately, many are short-lived, related to infection, food intolerance, or specific etiology. Those that persist or recur require greater attention on the part of the physician and can require psychiatric consultation. The frequency of consultation will depend in large part on the psychosocial sophistication and philosophy of care of the referring physician. When consulted, the child psychiatrist can complement the medical care by examination in greater detail of the psychosocial environment of the child, the family, and by psychiatric evaluation of the child. Formulation of these factors may then point the way to more helpful management of the child and treatment. The most serious problems, such as regional ileitis and ulcerative colitis, require not only collaboration of pediatricians and child psychiatrist, but surgeons as well if patients are to receive optimum care.     

Influence of tegaserod on proximal gastric tone and on the perception of gastric distention in functional dyspepsia

Background Abnormalities in gastric sensorimotor function (hypersensitivity to distention and impaired meal accommodation) have been implicated in the pathophysiology of functional dyspepsia (FD). To study the effect of the 5‐HT₄ agonist tegaserod on sensitivity to gastric distention and gastric accommodation in FD. Methods Thirty FD patients (7 males, mean age 42 ± 2 years) underwent a gastric barostat study on two separate occasions, 2 weeks apart, after 5 days of pretreatment with placebo or tegaserod 6 mg b.i.d. in a double‐blind randomized order. After introduction of the barostat bag, graded isobaric distentions (2 mmHg increments/2 min) were performed to determine gastric compliance and sensitivity to distention. Subsequently, the pressure level was set at intra‐abdominal pressure [minimal distending pressure (MDP)] + 2 mmHg for 90 min, with administration of a liquid meal (200 mL; 300 kcal) after 30 min. Key Results Tegaserod had no influence on MDP (7.9 ± 0.4 vs 7.4 ± 0.4 mmHg) or fasting gastric compliance (44 ± 10 vs 61 ± 6 mL mmHg^?1) and on fasting thresholds for first perception (3.6 ± 0.4 vs 4.2 ± 0.2 mmHg above MDP) or discomfort (9.9 ± 0.7 vs 10.5 ± 0.5 mmHg above MDP). Tegaserod did not alter intra‐balloon volumes before and after the meal [respectively 146 ± 14 vs 120 ± 11 and 297 ± 28 vs 283 ± 29 mL, not significant (NS)], or the amplitude of the meal‐induced gastric relaxation (151 ± 23 vs 162 ± 23 mL, NS). In the subgroup with normal gastric emptying (n = 22), tegaserod significantly enhanced meal‐induced accommodation (126 ± 23 vs 175 ± 29 mL, anova P < 0.001). Conclusions & Inferences Tegaserod does not alter gastric sensorimotor function in FD patients as a group. In the subgroup with normal gastric emptying, tegaserod 6 mg b.i.d enhanced gastric accommodation.