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Sodium phosphate preparation for colonoscopy: onset and duration of bowel activity.

BACKGROUND: Two doses of sodium phosphate are recommended for colonic cleansing before colonoscopy. Patients need information about the onset and duration of activity of the preparation. This study was designed to develop practical prescribing information to patients to reduce anxiety concerning bowel accidents. METHODS: Two hundred patients were requested to take a liquid diet the day before colonoscopy, to take 45 mL sodium phosphate with water or juice the evening before and the morning of the procedure, and to complete a questionnaire. RESULTS: Bowel activity began 1.7 hours (range 0.5 to 13) after the first dose and continued for 4.6 (1 to 14) hours. For the second dose the time to onset was 0.7 hours (0.25 to 4), and bowel activity continued for 2.9 hours (0.5 to 6.5). Bowel activity was completed 4 hours after ingestion of the second dose in 83% of patients and within 5 hours in 87%. Three of 200 patients reported the need for bowel evacuation during transit. CONCLUSIONS: The activity from the second dose of sodium phosphate starts and ends sooner than that from the first dose. When advising patients on when to take the second dose of sodium phosphate, 4 hours for most and 5 hours for those with long commutes, should provide adequate time for almost all patients to avoid bowel activity during travel.

Cathartics↗

Hypocalcemia and hyperphosphatemia after phosphate enema use in a child.

The authors present a 3-year-old girl in whom severe hyperphosphatemia and hypocalcemia developed after the administration of three adult-sized hypertonic phosphate enemas. The commonly held notion that these enemas are not absorbed and therefore are systemically inactive is incorrect. With early intervention and treatment, the child survived without sequelae despite a serum phosphate level (74.7 mg/dL) that is greater than those previously reported. The treatment of hyperphosphatemia is reviewed as well as underlying pathology such as altered gastrointestinal motility and renal insufficiency, which may predispose the patient to this problem. Physicians should be aware of the possible adverse effects that can be caused by hypertonic phosphate enemas.

Calcium Gluconate↗

Cisapride for the treatment of constipation in children: A double-blind study.

OBJECTIVE: To determine whether cisapride is effective in the treatment of children with constipation. STUDY DESIGN: Double-blind, placebo-controlled study in which children with chronic constipation were randomly assigned to treatment with cisapride or placebo for 12 weeks. RESULTS: Forty children were enrolled, and 36 completed the therapy. Treatment successes occurred in 13 of 17 (76%) subjects in the cisapride group and 8 of 19 (37%) subjects in the placebo group (P <.03). The odds ratio for response after cisapride administration was 8.2 times higher (95% CI 1.3 to 49.4). During cisapride therapy, there was a significant improvement in number of spontaneous bowel movements per week (from 0.9 +/- 0.1 to 4.1 +/- 1.1), and there was a significant decrease in number of fecal soiling episodes per day (1.8 +/- 0.5 to 0.08 +/- 0.4), percent with encopresis (82% vs 23%), number of laxative doses per week (from 10.3 +/- 2.6 to 0.8 +/- 0.6), percent using laxatives (77% to 24%), and total gastrointestinal transit time (from 115.0 +/- 3.7 hours to 77.0 +/- 11.1 hours). With placebo, there were no significant changes in the number of spontaneous bowel movements (from 1.0 +/- 0.8 to 2.2 +/- 0.6), percent with encopresis (74% vs 47%), or total gastrointestinal transit time (from 112.5 +/- 4.9 hours to 95.4 +/- 9.8 hours); but there was a significant decrease in number of fecal soiling episodes per day (from 1.3 +/- 0.4 to 0.4 +/- 0.2) and number of laxative doses used per week (from 11.5 +/- 2.9 to 2.05 +/- 0.7). The final number of spontaneous bowel movements, fecal soiling episodes, laxatives used, or percent patients with encopresis was not different when patients receiving cisapride were compared with those receiving placebo. CONCLUSION: Cisapride was effective in the treatment of children with constipation.

Adolescent↗

Gastroesophageal reflux: one reason why baby won't eat.

Gastroesophageal reflux (GER) is the movement of gastric contents retrograde into the esophagus. Sometimes the refluxate is seen as emesis, but often reflux is "silent," meaning that there are no discrete symptoms during an episode. In adults, the most common symptom of GER is heartburn, whereas in infancy excessive crying and malaise are symptoms that prompt investigation for GER, with or without esophagitis. Symptoms of esophagitis in infancy may include arching (hyperextension) of the torso and refusal of feedings. Tube feedings may be required to treat infants with failure to thrive who refuse oral feedings. Paradoxically, tube feedings increase the number of GER episodes. A hypothetical explanation for refusal of food in infancy is that pain with swallowing (odynophagia) or heartburn are consequences of peptic esophagitis. As a result, infants will learn to refuse food if it hurts or if they fear that it will hurt to eat. Another possible mechanism is visceral hyperalgesia, a neuropathic condition in which prior experience changes sensory nerves so that previously innocuous stimuli are perceived as painful. Some infants may have especially sensitive sensory nerves in the upper gastrointestinal tract, which predisposes visceral hyperalgesia to develop. Thus pain occurs from luminal distension or acid reflux in the absence of tissue damage. The evaluation of babies who won't eat includes a careful history and physical examination to exclude the possibility of chronic systemic illness. Refusal to feed is an unusual manifestation of a common condition: GER disease. The initial tests for GER usually include a barium swallow study to assess the upper gastrointestinal anatomy, endoscopy and esophageal biopsy to assess esophagitis, and an intraesophageal pH study, which is useful in "silent" reflux to quantitate the duration of esophageal acid exposure and to correlate discrete symptom episodes with periods of reflux. The treatment of infants and toddlers who refuse to eat because of pain resulting from visceral hyperalgesia or reflux esophagitis involves removing the pain associated with eating and making eating a pleasurable experience. Treatment for esophagitis may include maintaining an upright posture after meals and thickened feeds, medication to improve gastrointestinal motility or to decrease acid secretion, or fundoplication.

Esophagitis, Peptic↗

Advantages of fentanyl over morphine in analgesia for ventilated newborn infants after birth: A randomized trial.

OBJECTIVE: To compare the efficacy and adverse effects of fentanyl or morphine analgesia during the first 2 days of life in newborn infants who underwent mechanical ventilation. STUDY DESIGN: In a randomized double-blind trial, 163 infants were allocated to receive a continuous infusion of fentanyl (10.5 microg/kg over a 1-hour period followed by 1.5 microg/kg/hr) or morphine (140 microg/kg over a 1-hour period followed by 20 microg/kg/hr) for at least 24 hours. The severity of pain was assessed with physiological parameters, a behavioral pain scale, and stress hormone concentrations before and 2 and 24 hours after the start of treatment. RESULTS: The analgesic effect was similar in both groups, as judged by the pain scale. Plasma adrenaline and noradrenaline concentrations decreased significantly from 0 to 24 hours in both groups. Median adrenaline decrease was 0.5 nmol/L (interquartile range [IQR] 1.1;0.0) in the fentanyl and 0.7 nmol/L (IQR 1.3;0.1) in the morphine group, noradrenaline 2.1 nmol/L (IQR 9.0;0.2), and 3.0 nmol/L (IQR 7. 5;0.3), respectively. beta-endorphin decreased significantly only in the fentanyl group ( 14 pmol/L (IQR 28; 7), P <.05). Decreased gastrointestinal motility was less frequent in the fentanyl group (23% vs 47%, P <.01). CONCLUSIONS: With at least as effective analgesia as with morphine, fentanyl had fewer side effects. Fentanyl may be superior to morphine for short-term postnatal analgesia in newborn infants.

Analgesics, Opioid↗

Evoked cavernous activity.

PURPOSE: Corpus cavernosum electromyography has been widely done to evaluate autonomic dysfunction in patients with erectile dysfunction. We assessed the value of corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin responses for their accuracy in determining autonomic involvement in cases of erectile dysfunction. MATERIALS AND METHOD: We evaluated 75 men with erectile dysfunction by corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin response tests at our neurourology laboratory. The etiology of dysfunction was vascular, neurogenic, psychogenic or mixed based on a detailed medical and sexual history, physical examination, electrophysiological and laboratory studies, penile color Doppler ultrasonography, and cavernosography and/or cavernosometry. Autonomic involvement was clinically assessed by systemic findings, such as orthostatic hypotension, impaired gastrointestinal motility, sinus dysrhythmia and secretomotor changes. A concentric electromyography needle placed in the right cavernous body was used to record corpus cavernosum electromyography and evoked cavernous activity. The right median nerve was stimulated electrically with 13 to 16 mA. to determine evoked cavernous activity and the penile sympathetic skin response. The latter response was recorded with silver disc electrodes placed on the left cavernous body. All tests were performed using an electromyography/evoked potential machine. We determined the relationships among corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin response tests in respect to etiological factors. RESULTS: The 56 patients with normal corpus cavernosum electromyography activity had also evoked cavernous activity and a penile sympathetic skin response except for 1 with no penile sympathetic skin response but evoked cavernous activity. None of these patients had autonomic neuropathy. Of the 19 patients without corpus cavernosum electromyography activity 11 had evoked cavernous activity, including 10 with no autonomic neuropathy. The remaining 8 patients had no evoked cavernous activity, of whom 7 had autonomic neuropathy. A penile sympathetic skin response was recorded in 18 men with absent corpus cavernosum electromyography. CONCLUSIONS: Due to false-negative results on corpus cavernosum electromyography and penile sympathetic skin response testing evoked cavernous activity seems more reliable for determining autonomic involvement in the pathophysiology of erectile dysfunction.

Adult↗

Effects of transection and reanastomosis on postprandial jejunal transit and contractile activity.

BACKGROUND: The purpose of this study was to determine how transection and reanastomosis of the intestinal wall influences postprandial motor activity and transit in the small intestine. METHODS: Six dogs were each instrumented with 12 strain gauge transducers, two collection cannulas, and an infusion catheter defining a 100 cm study segment in the midjejunum. The animals underwent baseline measurements of postprandial motor activity and transit rate after 650 kcal solid and liquid meals. Postprandial motor activity was analyzed by computer methods that identify frequency, duration, amplitude, and propagation behavior of smooth muscle contractions. After the baseline measurements were performed, each animal underwent transection and reanastomosis of the intestinal wall at sites marked during the initial laparotomy. Measurements of postprandial motor activity and transit were repeated and compared with control values. RESULTS: Transection decreased frequency, amplitude, and percent propagation for postprandial contractions. Total propagating area per minute significantly decreased from 382 +/- 20 gram-seconds/minute to 190 +/- 66 gram-seconds/minute after transection (p < 0.05). Intestinal transit decreased from 13.5 +/- 1.5 cm/min to 8.5 +/- 2.4 cm/min (p < 0.05). The change in transit was related primarily to a change in frequency of propagating contractions (r = 0.767; p = 0.004). CONCLUSIONS: Transection and reanastomosis of the intestinal wall changes the temporal and spatial organization of contractions distal to the transection site. The net result is fewer distally propagating contractions and slower intestinal transit.

Anastomosis, Surgical↗

Upper and lower gastrointestinal motor and sensory dysfunction after human spinal cord injury.

This chapter describes the results of investigations of the upper and lower gastrointestinal tract in subjects with complete and incomplete spinal cord injury. In one study, gastric emptying was investigated and found delayed. The delay was tentatively attributed to a colo-gastric inhibitory reflex triggered by inappropriate colonic emptying. In another study, anorectal motor and sensory functions were measured. Decreased tone of the internal anal sphincter, exaggerated recto-anal reflexes following rectal distension and spontaneous high-amplitude rectal contractions at low distension volumes were among the findings of the study. Some of the subjects, classified as having a complete injury according to usual clinical criteria (American Spinal Injury Association, ASIA), reported sensation of distension of the rectum. This raises the issue of the need for better methods for the clinical assessment of sensory transmission in the spinal cord. Promising results obtained with functional magnetic resonance imaging of the brain during rectal stimulation in a small group of paraplegics, with complete injuries by ASIA criteria, showed evidence of activation of several brain regions.

Animals↗

Structural and functional aspects of acetylcholine peptide coexistence in the autonomic nervous system.

The present article is an attempt to briefly review acetylcholine and peptide coexistence in the ANS. For more detailed information the reader is referred to the book by Furness and Costa (1987) and books edited by Elfvin (1983) and Björklund et al. (1988). Acetylcholine is the "classical" transmitter substance between preganglionic and post-ganglionic neurons in both the sympathetic and parasympathetic nervous system but also between postganglionic parasympathetic neurons and effector cells. ENK and NT were early on shown to be present in preganglionic sympathetic neurons whereas SP and SOM have more recently been associated with these cells. Physiological experiments have shown that ENK may presynaptically inhibit cholinergic transmission in sympathetic ganglia. The cholinergic postganglionic parasympathetic neurons contain VIP/PHI. These peptides may be responsible for the atropine-resistant vasodilation seen after stimulation of parasympathetic nerves. In salivary glands VIP has been shown to potentiate the salivatory volume response to ACh. A number of postganglionic sympathetic neurons innervating exocrine sweat glands in the skin are also cholinergic. In addition to VIP/PHI, these neurons contain CGRP and probably also SP. The functional significance of acetylcholine coexisting with four vasodilatory peptides in this cell population is at present unclear. In the enteric ganglia the coexistence situation is very complex. Thus, in the myenteric plexus cholinergic SP-containing excitatory motor neurons seem to be present. In the myenteric plexus other cholinergic neurons may contain at least six different neuronal peptides. These latter neurons seem to be part of the peripheral intestino-intestinal reflex arc which is involved in regulation of gastrointestinal motility and mucosal functions. In the submucous plexus three populations of cholinergic neurons are present, one of which has secretomotor properties and contains CGRP, CCK, GAL, NPY and SOM. In vivo and in vitro studies have shown that developing sympathetic neurons can "change" the "classical" transmitter they-use and alter their neuropeptide expression. If dissociated sympathetic neurons are grown in cultures without any non-neuronal elements they differentiate into a noradrenergic phenotype. However, if the cultures also contain non-neuronal cells, both noradrenergic and cholinergic properties will develop. These changes may also by induced by a conditioned medium, containing a diffusible factor secreted from the non-neuronal cells. In conclusion, the present article underlines the complexity of the chemical neuroanatomy of the ANS and emphasizes the abundance of the peptides in both noradrenergic and cholinergic neurons. Although these peptides can be shown to exert a number of interesting effects in various experimental paradigms, much work is needed to define their exact role in nervous system function.

Acetylcholine↗

Endomorphins and related opioid peptides.

Opioid peptides and their G-protein-coupled receptors (delta, kappa, mu) are located in the central nervous system and peripheral tissues. The opioid system has been studied to determine the intrinsic mechanism of modulation of pain and to develop uniquely effective pain-control substances with minimal abuse potential and side effects. Two types of endogenous opioid peptides exist, one containing Try-Gly-Gly-Phe as the message domain (enkephalins, endorphins, dynorphins) and the other containing the Tyr-Pro-Phe/Trp sequence (endomorphins-1 and -2). Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2), which has high mu receptor affinity (Ki = 0.36 nM) and remarkable selectivity (4000- and 15,000-fold preference over the delta and kappa receptors, respectively), was isolated from bovine and human brain. In addition, endomorphin-2 (Tyr-Pro-Phe-Phe-NH2), isolated from the same sources, exhibited high mu receptor affinity (Ki = 0.69 nM) and very high selectivity (13,000- and 7500-fold preference relative to delta and kappa receptors, respectively). Both opioids bind to mu-opioid receptors, thereby activating G-proteins, resulting in regulation of gastrointestinal motility, manifestation of antinociception, and effects on the vascular systems and memory. To develop novel analgesics with less addictive properties, evaluation of the structure-activity relationships of the endomorphins led to the design of more potent and stable analgesics. Opioidmimetics and opioid peptides containing the amino acid sequence of the message domain of endomorphins, Tyr-Pro-Phe/Trp, could exhibit unique binding activity and lead to the development of new therapeutic drugs for controlling pain.

Amino Acid Sequence↗

Biochemistry and pharmacology of the endocannabinoids arachidonylethanolamide and 2-arachidonylglycerol.

The purpose of this review is to discuss the cellular synthesis and inactivation of two putative endogenous ligands of the cannabinoid receptor, N-arachidonylethanolamine (AEA) and 2-arachidonylglycerol (2-AG). Both ligands are synthesized by neurons and brain tissue in response to increased intracellular calcium concentrations. Both ligands are substrates for fatty acid amide hydrolase (FAAH). Both AEA and 2-AG bind to the neuronal form of the cannabinoid receptor (CB1). AEA binds the receptor with moderate affinity and has the characteristics of a partial agonist, whereas, 2-AG binds with low affinity but exhibits full efficacy. Two possible physiological roles of the endocannabinoids and the CB1 receptor are discussed: the regulation of gestation and the regulation of gastrointestinal motility.

Adjuvants, Immunologic↗

Irritable bowel syndrome.

Irritable bowel syndrome is a common gastrointestinal disorder characterized by abdominal pain and a change in bowel habits. It is estimated to occur in 9% to 22% of the US population, and is more often diagnosed in women than in men. There are no diagnostic markers for irritable bowel syndrome and no evidence of organic disease. Moreover, the pathophysiology is not completely understood; however, abnormal gastrointestinal motility, altered sensory activity, central neural dysfunction, psychological disturbances, and luminal factors have been proposed. Treatment requires a multifaceted approach. Education, dietary measures, fiber supplementation, and pharmacological and psychological interventions have been used in the management of this disorder.

Antidiarrheals↗

A second look at emepronium bromide in urinary incontinence.

Response to oral and intramuscular emepronium bromide was assessed cystometrically in nine patients with urinary incontinence caused by an uninhibited bladder. Oral therapy had no effect, whereas intramuscular administration increased bladder capacity and significantly delayed the onset of bladder spasm and the desire to void. Plasma-propranolol response was delayed and concentrations were reduced after an oral 40 mg dose of propranolol in 3 patients who had received oral emepronium bromide. These results indicate that although oral emepronium bromide had some anticholinergic effect--i.e., in reducing gastrointestinal motility--absorption of an oral dose was not sufficient for the bladder to be affected.

Administration, Oral↗

Abnormal vagal function in irritable bowel syndrome.

Alimentary and cardiac autonomic nervous function was assessed in 25 patients with the irritable bowel syndrome. The vagally mediated increase in lower oesophageal sphincter pressure induced by abdominal compression was below that of 25 controls in 13 patients. Efferent vagal function, assessed by the ratio of peak acid output after insulin-induced hypoglycaemia to maximal acid output after pentagastrin, was subnormal in 7 of 23 patients. Pulse rate variability with deep respiration was subnormal in 6 of 23 patients. Abnormality in these tests did not correlate closely with the presence of oesophagitis at endoscopy or with that of gastro-oesophageal reflux on pH monitoring. Thus abnormalities in autonomic nervous reflexes might account for the frequent occurrence of gastro-oesophageal reflux and may be involved in the production of disordered gastrointestinal motility in irritable bowel syndrome.

Adult↗

Ultrastructural observations of fibroblast-like cells forming gap junctions in the W/W(nu) mouse small intestine.

The ultrastructure of the wild-type (+/+) mice small intestine was compared with c-kit mutant (W/W(nu)) mice which only have few interstitial cells of Cajal (ICC) associated with Auerbach's plexus, in order to elucidate whether the specialized membrane contacts are general features of so-called fibroblast-like cells that are widely distributed in the tunica muscularis of the alimentary tract. Fibroblast-like cells in the Auerbach region were found in approximately equal number in W/W(nu) mice as in +/+ mice, while ICC associated with Auerbach's plexus (ICC-AP) could not be demonstrated in W/W(nu) mice in the present investigation. Fibroblast-like cells were characterized by cytoplasm of moderate to high electron density, well developed rough endoplasmic reticulum and nuclei with thick peripheral accumulations of heterochromatin. There were no basal lamina and caveolae along the cell membrane. It was observed that single fibroblast-like cells formed probable small gap junctions with muscle cells of both circular and longitudinal layers. Fibroblast-like cells with the same features were also observed in the region of the deep muscular plexus in both +/+ and W/W(nu) mice. The present observation, together with our previous studies on rats and guinea-pigs, suggest the common presence of gap junctions or gap junction-like structures on fibroblast-like cells in the gastrointestinal musculature and their involvement in the regulatory system of gastrointestinal motility by passing electrical or molecular signals to influence the state of muscle tonus.

Animals↗

Association of autonomic nervous hyperreflexia and systemic inflammation in patients with Crohn's disease and ulcerative colitis.

The autonomic nervous system modulates gastrointestinal motility, secretion and mucosal immunity. Its dysfunction may be of pathogenetic importance in inflammatory bowel disease (IBD). This study aimed at investigating the autonomic nervous function in patients with IBD. Forty-seven patients with IBD, 28 with Crohn's disease (CD) and 19 with ulcerative colitis (UC), were investigated by means of 5 cardiovascular and 2 pupillary standardized autonomic nervous function tests. In CD and UC, cardiovascular autonomic neuropathy was very rare (0%, 5%), whereas pupillary autonomic neuropathy was more prevalent (21%, 21%). In contrast to autonomic neuropathy, overall cardiovascular (CD: 29%, UC: 26%) and pupillary autonomic hyperreflexia (46%, 37%) were found more often. Patients with CD and UC demonstrated elevated percentiles in the respiratory sinus arrhythmia test as compared to controls (RSA: 82.3 +/- 3.9%, 80.0 +/- 5.9%, controls: 50.0% +/- 1.5%, p < 0.0001). CD patients with, as compared to patients without, RSA hyperreflexia had significantly higher CDAIs (p < 0.001), increased erythrocyte sedimentation rates (p < 0.005) and more often extraintestinal disease manifestations (p < 0.001). UC patients with, as compared to patients without, pupillary latency time hyperreflexia had lower hemoglobin (p < 0.05), lower albumin (p < 0.01) and increased erythrocyte sedimentation rates (p < 0.05). Autonomic hyperreflexia was significantly associated with more severe inflammation and systemic disease in IBD. Hyperreflexia may be a response to inflammation or a pathogenetic element that drives mucosal inflammation.

Adolescent↗

Inhibitory effect of nociceptin on somatostatin secretion of the isolated perfused rat stomach.

The heptadecapeptide nociceptin/orphanin FQ (N/OFQ) has recently been isolated from porcine and rat brain and identified as the endogenous ligand of the N/OFQ receptor (NOP). It shows structural similarity with opioid peptides. N/OFQ has also been demonstrated in the gastrointestinal tract, where it inhibits gastrointestinal motility. The effect of N/OFQ on gastric neuroendocrine function is unknown as yet. In the isolated perfused rat stomach, N/OFQ 10(-6) M shows a small, but not significant decrease of basal somatostatin (SRIF) secretion. At the doses of 10(-12) M, 10(-10) and 10(-8) M N/OFQ has neither an effect on basal SRIF nor on basal vasoactive intestinal polypeptide (VIP), gastrin, substance P or bombesin secretion, respectively. However, gastric inhibitory polypeptide (GIP) 10(-9) M prestimulated SRIF secretion is significantly inhibited by N/OFQ 10(-8) M (-45+/-11%; p<0.05 vs. GIP). During concomitant infusion of the specific competitive NOP receptor antagonist [Nphe(1)]nociceptin(1-13)NH(2) 10(-6) M, the effect of N/OFQ is abolished (6+/-11%; p<0.05 vs. GIP and N/OFQ) while the opiate receptor antagonist naloxone 10(-6) M has no significant effect (-32+/-9%; ns vs. GIP and N/OFQ). At the higher concentration of N/OFQ 10(-6) M, the inhibition of prestimulated SRIF secretion (-58+/-6%; p<0.05 vs. GIP) is not influenced by the NOP receptor antagonist at the concentration of 10(-6) M (-49+/-9%; ns vs. GIP and N/OFQ) and 10(-5) M (-69+/-10%; ns vs. GIP and N/OFQ), respectively. On the other hand, infusion of naloxone 10(-6) M attenuates the inhibitory effect of N/OFQ 10(-6) M significantly (-21+/-6%; p<0.05 vs. GIP and N/OFQ).Thus, N/OFQ is an inhibitor of gastric somatostatin secretion. At the lower dose, this effect is transmitted via NOP receptors, while at the higher dose of 10(-6) M, the effect is at least in part mediated via opiate receptors.

Animals↗

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