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PubMed2001

Differences in the distribution and chemical coding between neurons in the inferior mesenteric ganglion supplying the colon and rectum in the pig.

The distribution and chemical coding of neurons in the porcine left and right inferior mesenteric ganglion projecting to the ascending colon and rectum have been investigated by using combined retrograde tracing and double-labelling immunohistochemistry. The ganglion contained many neurons supplying both gut regions. The colon-projecting neurons (CPN) occurred exclusively in the cranial part of the ganglia where they formed a large cluster distributed along the dorso-lateral ganglionic border and a smaller cluster located close to the caudal colonic nerve output. The rectum-projecting neurons (RPN) formed a long stripe along the entire length of the lateral ganglionic border and, within the right ganglion only, a small cluster located close to the caudal colonic nerve output. Immunohistochemistry revealed that the vast majority of the CPN and RPN were noradrenergic (tyrosine-hydroxylase-positive). Many noradrenergic neurons supplying the colon contained somatostatin or, less frequently, neuropeptide Y. In contrast, a significant subpopulation of the noradrenergic RPN expressed neuropeptide Y, whereas only a small proportion contained somatostatin. A small number of the non-adrenergic RPN were cholinergic (choline-acetyltransferase-positive) and a much larger subpopulation of the nerve cells supplying both the colon and rectum were non-adrenergic and non-cholinergic. Many cholinergic neurons contained neuropeptide Y. The non-adrenergic non-cholinergic neurons expressed mostly somatostatin or neuropeptide Y and some of those projecting to the rectum contained nitric oxide synthase, galanin or vasoactive intestinal polypeptide. Many of both the CPN and RPN were supplied with varicose nerve fibres exhibiting immunoreactivity against Leu5-enkephalin, somatostatin, choline-acetyltransferase, vasoactive intestinal polypeptide or nitric oxide synthase The somatotopic and neurochemical organization of this relatively large population of differently coded inferior mesenteric ganglion neurons projecting to the large bowel indicates that these cells are probably involved in intestino-intestinal reflexes controlling peristaltic and secretory activities.

Animals↗
PubMed1989

Trypanosoma cruzi: quantitative studies of development of two strains in small intestine and rectum of the vector Triatoma infestans.

This paper describes the development stages and numbers of flagellates of two strains of Trypanosoma cruzi living in the small intestine and rectum of the insect, Triatoma infestans, during the first 12 weeks postinfection (pi). Mainly epimastigotes and occasionally amastigotes and final trypomastigotes developed in the small intestine but after starvation periods of 3 or 4 weeks higher percentages of spheromastigotes including their transitional forms to/from epimastigotes were found. In the rectum, the percentage of final trypomastigotes increased in two steps; the second, but not the first, correlated with the development of intermediates originating from epimastigotes. For both strains the total number in the small intestine increased during the first 8 or 9 weeks, although there were reduced numbers when the bugs had starved for 3 or 4 weeks. In the rectum the numbers increased up to 10 weeks pi; only about 25% of these lived in the lumen, the others were located at the rectal wall. In small intestine and rectum the "Chile 5" strain of T. cruzi (zymodeme 1) nearly always reached higher population densities than the "Chile 7" strain (zymodeme 2).

Animals↗
PubMed1995

Posterior plication of the rectum for rectal prolapse in children.

Fourteen patients with rectal prolapse (age range, 1 to 12 years) underwent posterior plication of the rectum for rectal prolapse. The procedure consisted of (1) natal cleft incision, (2) midline separation of the levator muscle, (3) dissection of two thirds of the circumference of the rectum, (4) plication of the posterior wall of the rectum using U-shaped mattress sutures, and (5) fixation of the sutures of the rectal wall to the coccyx. There has been no recurrence of prolapse in any of the patients. The authors' experience suggests that an elongated rectum is responsible for prolapse. This simple but definitive technique is recommended.

Child↗
PubMed1994

Circulation of estrogens introduced into the rectum or duodenum in pigs.

To determine the absorption and metabolism of 17 beta-estradiol (E2) by the rectum of the pig, 10 mg of crystalline E2 was placed in the rectum of prepubertal gilts in Experiment 1. Blood samples were subsequently obtained from hepatic portal and jugular veins and plasma was assayed for E2, estrone (E1), 17 beta-estradiol-glucuronide (E2G), estrone-glucuronide (E1G) and estrone-sulfate (E1S). Concentrations of E2, E1, E2G, E1G, and E1S rose in the hepatic portal vein within 30 min and remained elevated for several hr. Concentrations of E2 in the hepatic portal vein represented 3% of the total estrogen detected in the hepatic portal vein during the 5 hr sampling period, indicating that most of the E2 was metabolized prior to entering the hepatic portal vein after absorption by the rectal mucosa. Concentrations of E2, E1, E2G, E1G, and E1S rose in the jugular vein and remained elevated for several hr. The rise in E2 and E1 in the jugular vein may have come from E2 and E1 in venous circulation from the rectum that entered the inferior vena cava bypassing the hepatic portal vein and liver. The net result of absorption of E2 from the rectum of gilts was a large rise in unconjugated and conjugated E2 and E1 in the peripheral circulation. In Experiment 2 prepubertal gilts fitted with jugular, hepatic portal, duodenal, and gall bladder catheters were infused into the duodenum with bile from pregnant gilts. Concentrations of E2, E1, E2G, and E1G were determined in gallbladder bile of gilts before infusion and at 470 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Rectal↗
PubMed2004

Caustic burns of rectum and colon in emergencies.

BACKGROUND: Because of their rarity, chemical burns of rectum and colon have been poorly studied. This clinical report studies the epidemiologic, diagnostic, and therapeutic features of rectal and colonic burns after enema with caustics. METHODS: This is a retrospective clinical report of a personal series of 21 patients admitted in our hospital from January 1990 to January 2000 for an acute chemical colitis after enema. RESULTS: Inpatient prevalence: 0.04%. Mean age: 29.7 +/- 12 years (range 17 to 19). Sex ratio: 16 female and 5 male. Circumstances: suicide (n = 14), abortion (n = 3), murder (n = 3), mistake (n = 1). Responsible caustic: sulphuric acid (n = 12), chlorhydric acid (n = 5), potash (n = 2), unknown acid (n = 1), plant decoction (n = 1). Injected quantity: 50 to 250 mL. Ten patients suffered light damage and had an early favorable course under medical treatment, 8 of them had a secondary rectal-sigmoid stenosis. Eleven patients presented with severe necrotic damage, of difficult and often delayed diagnosis based on an enduring symptomatology without clear peritoneal syndrome. Upon surgery, necrotic damage spread on rectum and sigmoid colon (n = 2), up to the transverse colon (n = 4), to the right colonic angle (n = 3), to the right colon (n = 2); once a 10 cm long necrosis of the ileum was associated (n = 1); only 1 patient had a colonic perforation. Performed surgery: 11 resections of necrotic colon and proximal colostomy (Hartman operation). Mortality: 6 patients. Morbidity: 3 of 5 patients. CONCLUSIONS: Chemical burns of rectum and colon produced by strong acid or basic products are necrotizing lesions whose gravity is often hidden by the absence of peritoneal inflammation signs, thus mortality is high. Only early surgery is likely to improve the poor prognosis of severe chemical damage of the rectum and colon.

Abortion, Illegal↗
PubMed2004

[Colorectal stapled anastomosis: results after anterior resection of the rectum for cancer].

OBJECTIVE: Stapled end to end anastomosis makes the restoration of digestive continuity at the level of lower pelvis easier, but carries a certain risk. The aim of this report was to evaluate this risk in terms of immediate results and tumor recurrence after surgery for rectal cancer. PATIENTS AND METHODS: The data of 301 patients operated on following this technique between 1980 and 2000 have been reviewed in order to analyse the tumor characteristics, the operation and associated complications, the immediate postoperative complications and recurrence rate. RESULTS: Among the 301 patients (192 males and 109 females) with median age of 66 years, 19 (6.3%) received an emergency operation due to bowel obstruction. The rectal adenocarcinoma was located in the upper rectum in 132 cases (43.8%), in the middle rectum in 141 cases (46.8%) and in the lower rectum in 19 cases (9.4%). Preoperative radiotherapy was carried out in 148 cases (49%): between 1987 and 1996 with a dose of 30 Grays (Gy), later increased to 39 Gy and 45 Gy in 12 cases. From 1990, 113 patients have received adjuvant chemotherapy for stage III and IV tumors and in some position cases for stage II tumor. The excision left a safety margin under the tumor of less than 2 cm in 59 cases (19.6%), and the anastomosis was located at 5 cm or less from the anal verge in 178 cases (59%). Primary defunctioning stoma was formed in 39 cases (13%). An anastomotic defect was observed during the operation in 18 cases (6%) and 26 fistulas occured postoperatively (7.6%), significantly related to the location of the anastomosis with regard to the anal verge (P = 0.0009). The hospital mortality was 8 cases (2.6%). Cases of stenosis were uncommon : 11 cases (3.6%), significantly associated with preoperative radiotherapy (P =0.02). The local recurrence rate was 12% (37 cases) in a median time delay of 16 months, essentially related to the tumor stage (P = 0.004) and the considered period (P = 0.001). CONCLUSION: Stapled end-to-end colorectal anastomosis after excision of rectum for cancer is a reliable technique with a low rate of complication and tumor recurrence, when the surgical procedure is included in the curative therapy management of cancer.

Adenocarcinoma↗
PubMedDate not supplied

Outcome after rectum or sigmoid resection: a review for gynecologists.

It remains unclear when to perform a discoid or segmental bowel resection for large endometriotic nodules with intestinal invasion. Moreover, endometriosis series are rather small to fully evaluate functional consequences of bowel resection. We therefore reviewed the incidence of leakage and functional problems after anterior and sigmoid resection as reported in the surgical literature albeit for other indications. Endoscopic resection clearly is feasible but requires an experienced surgeon. The incidence of leakage is not different after hand-sewn or stapled anastomosis, but is higher after a low rectum resection than after a sigmoid resection. Similarly, functional bowel problems are higher after a low rectum resection than after sigmoid resection. Low rectum resection in addition can be associated with functional bladder problems and sexual disturbances as anorgasmia. In conclusion, short- and long-term complications are much higher after a low rectum than after a sigmoid resection. This seems to be important in making the decision to perform a discoid or a segmental bowel resection for severe endometriosis.

Anastomosis, Surgical↗
PubMed1996

Inadvertent perforation of the rectum during abdominoperineal resection.

BACKGROUND: Intraoperative inadvertent perforation of the rectum is a potentially avoidable complication of abdominoperineal resection (APR). Although widely thought to be detrimental, the impact of inadvertent perforation on outcome has not been conclusively determined, especially after controlling for potential confounding variables. The objective of this study was to determine if inadvertent perforation of the rectum during APR for rectal cancer is an independent risk factor for the adverse outcomes of local recurrence and/or death. METHODS: This retrospective cohort study included all patients who underwent APR for primary adenocarcinoma of the rectum at a single teaching hospital from 1980 to 1990. Data were obtained regarding patient demographics, presence of inadvertent perforation, histopathological characteristics, adjuvant therapy, local recurrence, and survival. RESULTS: Of 178 patients included in the study, 42 (24%) had inadvertent perforation. By univariate analysis, local recurrence was significantly higher in the perforated group than the nonperforated group (54% vs 17%; P < 0.001). Similarly, 5-year survival was significantly decreased with inadvertent perforation (29% vs 59%; P = 0.003). Multivariate analysis controlling for stage, grade, age, sex, and adjuvant therapy showed inadvertent perforation to be an independent risk factor for both increased local recurrence and decreased 5-year survival (Hazard Ratio for each model). CONCLUSIONS: Inadvertent perforation of the rectum during APR is associated with increased local recurrence and decreased 5-year survival. The detrimental implications of inadvertent perforation during APR mandates meticulous avoidance.

Adenocarcinoma↗
PubMed1998

Differential effect of radiation on endothelial cell function in rectal cancer and normal rectum.

BACKGROUND: Chronic radiation injury of the intestine is associated with significant underexpression of a potent physiological anticoagulant, endothelial cell thrombomodulin (TM). This study compared early and late radiation-induced changes in endothelial TM, urokinase plasminogen activator (uPA), and transforming growth factor beta (TGF-beta) in normal rectum and tumors. METHODS: Rectal resection specimens from 27 patients were analyzed: Nine patients underwent primary resection of rectal cancer, 11 tumors were resected after neo-adjuvant radiotherapy, and 7 because of local recurrence after prior resection and adjuvant radiotherapy. TM, uPA, and extracellular matrix-associated TGF-beta, immunoreactivity were assessed using computerized image analysis. RESULTS: Multivariate analysis revealed that tumors had more TM-positive vessels (P = 0.003), more uPA-positive cells (P <0.001), and higher TGF-beta immunoreactivity levels (P <0.001) than normal rectum. Preoperative irradiation was associated with decreased proportions of TM-positive vessels in tumors (P = 0.003) and normal rectum (P <0.001). Irradiated tumors had fewer uPA-positive cells (P = 0.003) and less TGF-beta immunoreactivity (P = 0.001) than unirradiated tumors. The proportion of TM-positive vessels in irradiated rectum from patients with recurrence was decreased (P = 0.03), whereas the recurrent (ie, unirradiated) tumors did not differ from primary tumors in terms of TM, TGF-beta, or uPA immunoreactivity. CONCLUSIONS: The results support a role for endothelial dysfunction in the pathogenesis of radiation proctitis. Maintaining endothelial cell anticoagulant function may be a potential method to optimize the therapeutic ratio of adjuvant radiotherapy of rectal cancer.

Aged↗
PubMed1997

Anatomy of the nerve supply of the rectum, bladder, and internal genitalia in anorectal dysgenesis in the male.

Using a posterior sagittal approach to expose retroperitoneal viscera and nerves, the anatomy of the pelvic autonomic nerve plexus was studied in normal and abnormal male cadaver specimens. This plexus is found on the anterolateral surface of the lower rectum surrounded by endopelvic fascia. The autonomic nerves that supply the plexus reach it from posterior, lateral to the midline by passing over the surface of the rectum. The nerves of this plexus are distributed with the terminal branches of the internal iliac arteries, mainly with the vessels of the inferior vesical plexus. The rectum receives its autonomic nerves with its arterial blood supply, the superior rectal artery. The nerves of the pelvic plexus supply the genitourinary viscera that lie anterior to the rectum and in front of the fascia of Denonvilliers. The named fascial layers of the pelvis play a major role in determining the anatomic plane of these structures. In anorectal agenesis the plexus becomes a more midline structure. Because the pelvic fascia is often deficient in these cases these nerves lie vulnerable to inappropriate midline dissection.

Anal Canal↗
PubMed2001

Effect of age on radiation-induced early changes of rat rectum. A histological time sequence.

BACKGROUND AND PURPOSE: Radiation treatment of the elderly (> 75 years) is often modified due to an assumed decrease in normal tissue tolerance in this age group. Since more radiobiological data concerning normal tissue toxicity as a function of age are needed, a histological study of age-related radiation changes of the rectum was performed. MATERIALS AND METHODS: The rectum of young and old female Wistar rats (12 and 78 weeks, respectively) was irradiated with single doses of 22 and 39 Gy. The field size was 1.5 x 2.0 cm. The animals were sacrificed at 1, 2, 4 and 10 weeks after treatment. To evaluate radiation damage, 12 histological parameters were scored in four areas of the rectum. A total radiation injury score was calculated. The number of proliferative epithelial cells was evaluated by 5-bromo-2'-deoxyuridine labeling. RESULTS: Some age-related histological differences were observed; especially, the incidence of ulceration and vascular occlusion was higher in the older group. In the low dose group of the older animals, 60% showed ulceration, which was 0% for the young low dose animals. Severe vascular changes occurred early and were more extensive in older animals (4 weeks) than in the younger group (10 weeks). In the area adjacent to the treatment field, cell proliferation increased significantly in older rats at 1 week after 22 Gy, which did not occur in the young group. CONCLUSIONS: Discrete radiation-induced histological differences were observed between the rectum of young and old Wistar rats, especially in the development of ulceration and vascular changes. Although the survival of these Wistar rats in earlier studies was not affected by age, the impact of the observed histological differences for their importance in the long-term is currently being investigated.

Age Factors↗
PubMed2000

Presence of pituitary adenylate cyclase-activating polypeptide (PACAP) and its relaxant activity in the rectum of a teleost, the stargazer, Uranoscopus japonicus.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide and a member of the secretin/glucagon superfamily of peptides that include vasoactive intestinal polypeptide. PACAP is not only present in the central nervous system but also in peripheral organs, such as the gastrointestinal tract, gonads and adrenal glands, and plays various roles in mammals. Recently, we isolated and characterized PACAP, which is very similar to PACAP of mammalian origin, from the brain of a teleost, the stargazer, Uranoscopus japonicus. In the present study, the expression of PACAP mRNA was detected in the stargazer rectum using the reverse transcriptase/polymerase chain reaction (RT-PCR) method. The distribution of PACAP-like immunoreactivity in the rectum was also examined immunohistochemically, using an antiserum raised against PACAP 27, and PACAP-like immunoreactive neuronal cell bodies and fibers were found in the myenteric plexuses and the smooth muscle layers of the rectum. The present study also investigated the relaxant activity of synthesized homologous PACAP on rectal contraction. Stargazer PACAP, like that of mammalian origin, inhibited contractions stimulated by acetylcholine or potassium chloride. PACAP-induced inhibition was not affected by preincubation with atropine, propranolol, or phentolamine. These results suggest that PACAP may act directly as an inhibitory neuropeptide in the stargazer rectum.

Acetylcholine↗
PubMed1997

Dose-volume histograms for bladder and rectum.

PURPOSE: A careful examination of the foundation upon which the concept of the Dose-Volume Histogram (DVH) is built, and the implications of this set of parameters on the clinical application and interpretation of the DVH concept has not been conducted since the introduction of DVHs as a tool for the quantitative evaluation of treatment plans. The purpose of the work presented herein is to illustrate problems with current methods of implementing and interpreting DVHs when applied to hollow anatomic structures such as the bladder and rectum. METHODS AND MATERIALS: A typical treatment plan for external beam irradiation of a patient with prostate cancer was chosen to provide a data set from which DVH curves for both the bladder and rectum were calculated. The two organs share the property of being shells with contents that are of no clinical importance. DVHs for both organs were computed using a solid model and using a shell model. Typical treatment plans for prostate cancer were used to generate DVH curves for both models. The Normal Tissue Complication Probability (NTCP) for these organs is discussed in this context. RESULTS: For an eight-field conformal treatment plan of the prostate, a bladder DVH curve generated using the shell model is higher than the corresponding curve generated using the solid model. The shell model also has a higher NTCP. A six-field conformal treatment plan also results in a higher DVH curve for the shell model. A treatment plan consisting of bilateral 120-degree arcs, results in a higher DVH curve for the shell model, as well as a higher NTCP. CONCLUSION: The DVH concept currently used in evaluation of treatment plans is problematic because current practices of defining exactly what constitutes "bladder" and "rectum." Commonly used methods of tracing the bladder and rectum imply use of a solid structure model for DVHs. In reality, these organs are shells and the critical structure associated with NTCP is obviously and indisputably the shell, as opposed to its contents. Treatment planning algorithms for DVH computation should thus be modified to utilize the shell model for these organs.

Humans↗
PubMed2003

Dextrose is absorbed by rectum in hypoglycemic rats.

The objective of this study was to determine the efficacy of the rectal administration of dextrose in raising the serum glucose in a hypoglycemic rat model. A randomized, prospective, controlled experimental study was performed using 18-h fasted, acutely anesthetized Harlan Sprague-Dawley rats made hypoglycemic by the intravenous infusion of insulin at 3 U/kg/h for 2 h. At 1 h into the infusion, study rats received 1, 2, or 3 g/kg of 50% dextrose solution infused into the rectum using a balloon tipped catheter. Control animals received an equivolume, equi-osmolar (as compared to the 3 g/kg dose) amount of polyethylene glycol (PEG)-400 by rectum. Blood glucose (BG) measurements were made using blood obtained from the portal vein and a femoral artery. Intravenous insulin administered at 3 U/kg/h consistently produced BG levels 60% of baseline at 60 min and 80% of baseline at 120 min. BG levels in portal and arterial circulation increased after rectal dextrose. In general, portal venous values were greater than arterial after rectal dextrose. The greatest increase was seen 30 min after dextrose by rectum in animals receiving 3 g/kg. A 50% dextrose administered by rectum in hypoglycemic rats is absorbed in quantities sufficient to raise BG in the arterial and portal circulation.

Administration, Rectal↗
PubMed2002

Early and late effects of irradiation on morphometry and residual strain of mouse rectum.

Radiotherapy of malignancies in the pelvis is associated with both early and late intestinal reactions with subsequent alterations in rectal function because this part of the intestine often is included in the radiation field. This report presents data on morphometry of the zero-stress and no-load states as well as residual strains and opening angles of the rectum in mice with early and late radiation injury and in age-matched sham-irradiated control groups. In blood vessels and esophagus, cross-sections at the zero-stress state are not closed rings, but open sectors. The rectal zero-stress state is demonstrated by cutting the rectum into rings and cutting the rings into sectors; each sector is characterized by an opening angle. The opening angle was between 50 degrees and 200 degrees and differed between groups (P < 0.01). Young mice had 25-50% smaller opening angles than the older mice. The irradiated groups had 25-75% smaller opening angles than the normal groups. The residual strain analysis showed mucosal compression and serosal tension in the no-load state. Both at the serosal and mucosal surfaces, variation was found between groups (P < 0.01). The no-load state wall thickness-to-mucosal circumferential length ratio varied along the axis of the organ (P < 0.01) and between groups (P < 0.01). The early irradiated group had higher values than the control group. Furthermore, proximal to the irradiated zone the late irradiated group had significantly higher values compared to the normal group, indicating a higher stress level proximal to the irradiated zone. The zero-stress state must be taken into account when studying pathophysiological problems in which the stresses and strains are important, eg, the storage function of the rectum. Radiation therapy and age remodeled the morphometry and zero-stress state of rectum.

Animals↗
PubMed1993

Absorption of 2',3'-dideoxyinosine from lower gastrointestinal tract in rats and kinetic evidence of different absorption rates in colon and rectum.

This study explored the rectal route of administration for 2',3'-dideoxyinosine (ddI). Rats were given a rectal infusion of nonradiolabeled ddI (200 mg/kg in 0.7 mL saline) over 35 min along with an intravenous (iv) bolus injection of [8-(3)H]ddI (20 microCi, equivalent to 2.1 micrograms), which was used to calculate the absolute rectal bioavailability of ddI. Maximal plasma concentrations of rectally administered unlabeled ddI were 5.4 +/- 2.2 micrograms/mL and were reached at the end of the infusion. The rectal bioavailability averaged 15.6 +/- 4.4% (n = 9). The second aim of this study was to examine the kinetics of ddI absorption from the colorectal region. Analyses of the absorption rate-time profiles by the Loo-Riegelman and deconvolution methods showed biphasic absorption: a rapid phase during infusion and a slow phase postinfusion. These profiles were inconsistent with a mammillary model with absorption from a single site with one apparent rate constant. The model which gave the best fit for infusion and postinfusion data consisted of two different sites (colon and rectum) with different apparent absorption rate constants. The two sites were connected by a first-order transfer of drug solution from rectum to colon. The apparent absorption rate constant in the rectum was 39-fold higher than that in the colon. In conclusion, these results show absorption of ddI from the colorectal region and suggest the rectal route as an alternative to the oral route. The data further suggest different absorption sites in the colorectal region, with a more rapid absorption in the rectum than in the colon.

Administration, Rectal↗
PubMed1998

Perirectal graciloplasty: a novel surgical technique for the treatment of the neurogenic rectum and rectal inertia.

A novel technique for evacuation of the denervated rectum was carried out on 11 mongrel dogs (mean weight 15.8 +/- 4.6 kg). The gracilis muscle was mobilized from the thigh, pedicled on its origin from the pubic ramus, and was introduced into the ischiorectal fossa through a para-anal incision. The abdomen was opened and the rectum mobilized and wrapped with the gracilis muscle which was pulled through the ischiorectal fossa into the pelvis. Rectal denervation was induced by bilateral pelvic ganglionectomy; cystostomy was performed owing to the resultant vesical denervation. Two electrodes were sutured to the gracilis muscle and connected to a myostimulator. The effect of electrostimulation of the gracilis muscle on the rectal and rectal neck (anal canal) pressures and on balloon expulsion was determined. Gracilis muscle stimulation with a burst of 30 Hz during 300 msec with a stimulus of 0.5 msec and an intensity just suprathreshold effected a rectal pressure rise (P < 0.001) with no rectal neck pressure change (P > 0.05); balloon expulsion occurred at a mean balloon filling of 14.8 +/- 3.2 mL. Gracilis muscle transposition could be a suitable experimental model for evacuation of the neurogenic rectum. The technique might be considered for the treatment of the neurogenic rectum, or rectal inertia.

Animals↗
PubMed1999

Pain produced by electric stimulation of the rectum in patients with irritable bowel syndrome: further evidence of visceral hyperalgesia.

BACKGROUND: Visceral hyperalgesia is most likely a phenomenon of substantial clinical importance and may also play a role in the pathophysiology of the irritable bowel syndrome (IBS). We investigated the manifestation of visceral hyperalgesia in IBS patients by nociceptive electric stimulation of the rectosigmoid junction and rectum. METHODS: Twelve IBS patients fulfilling the Rome criteria and 9 healthy controls were studied. Visceral single and repeated electric burst stimuli were applied with a bipolar electric stimulator inserted through the sigmoidoscope. The sensation (ST) and pain detection (PDT) thresholds were determined in response to single and repeated stimuli at the rectosigmoid junction, and PDT to repeated stimuli at four different positions in the rectum. Cutaneous single and repeated electric stimuli were applied to the lateral aspect of the foot, determining ST and PDT. RESULTS: Cutaneous stimulation showed no significant differences for ST and PDT between patients and controls. The rectosigmoid junction showed significantly lower ST for single stimuli (P<0.01) and a significantly lower PDT for single and for repeated stimuli (P<0.05 and P<0.02) in IBS patients. In the rectum the IBS patients had a significantly lower PDT than controls (P<0.001). CONCLUSIONS: For cutaneous electric stimulation no differences in the pain thresholds between the two groups were found, showing that there is no generalized hyperalgesia in IBS patients. The IBS patients had a specific decrease of the pain thresholds in the rectum and rectosigmoid junction, indicating visceral hyperalgesia. These results point to central visceral hyperexcitability as an important factor in the pathophysiology of IBS.

Abdominal Pain↗