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PubMed2002

Impaired gastrocolonic response and peristaltic reflex in slow-transit constipation: role of 5-HT(3) pathways.

Colonic motility is modulated by the 5-hydroxytryptamine (5-HT)(3)-dependent gastrocolonic response and 5-HT(3)-independent peristaltic reflex. We compared descending colon tone responses to antral distension, duodenal lipid perfusion, and colonic distension after double-blind placebo or granisetron in 13 healthy volunteers and nine slow-transit constipated patients. Antral distension (100-300 ml) and duodenal lipids (3 kcal/min) evoked increases in colon tone in volunteers, which were blunted in constipated patients (P < 0.05). Granisetron (10 microg/kg) reduced responses to antral distension and lipids in volunteers and to lipids in constipated patients (P < 0.05). The ascending contraction of the peristaltic reflex was blunted in constipated patients (P < 0.05), whereas descending responses were similar. Granisetron did not modify the peristaltic reflex. Colonic responses to bethanechol were similar in patients and volunteers. In conclusion, antral distension- and duodenal lipid-activated gastrocolonic responses and ascending contractions of the peristaltic reflex are impaired with slow-transit constipation with loss of both 5-HT(3)-dependent and -independent function. Thus abnormalities of neural reflex modulation of colonic motor function may play pathophysiological roles in slow-transit constipation.

Adult↗
PubMed1997

Intravenous butyrate and healing of colonic anastomoses in the rat.

PURPOSE: Intracolonic infusions of short chain fatty acids promote healing of colonic anastomoses. Because the intravenous route may have wider clinical application, we studied the effect of intravenous n-butyrate on the mechanical strength of colonic anastomoses in the rat. METHODS: After placement of an indwelling intravenous catheter, the descending colon was transected and an anastomosis was performed. Rats were then randomized to receive total parenteral nutrition (TPN group; n = 15) or total parenteral nutrition plus 130 mM/l of n-butyrate (TPN+BUT group; n = 13). On the fifth postoperative day, bursting pressure and bowel wall tension of the anastomoses were measured in situ. Anastomotic tissues were analyzed for hydroxyproline. RESULTS: The TPN+BUT group had a significantly higher bursting pressure (107.5 +/- 30.3 vs. 83 +/- 41.0 mmHg; P = 0.04) and bowel wall tension (20.7 +/- 7.6 vs. 14.1 +/- 9.9 Newton; P = 0.03). Tissue hydroxyproline was not different between the two groups (TPN, 45.8 +/- 9.2, and TPN+BUT, 47.9 +/- 2.9 microg/mg tissue nitrogen). CONCLUSIONS: We conclude that intravenous butyrate improves mechanical strength of a colonic anastomosis without a detectable change in total collagen content.

Anastomosis, Surgical↗
PubMed1977

Colonic necrosis complicating pancreatitis.

Bowel necrosis is an uncommon complication of pancreatitis. Two patients are reported who developed ileocecal and descending colon changes as a result of ischemia following severe pancreatitis. Arteriography in one patient confirmed the presence of intraluminal thrombi.

Acute Disease↗
PubMed1998

Moderation of lactulose-induced diarrhea by psyllium: effects on motility and fermentation.

Psyllium has been reported to inhibit lactulose-induced colonic mass movements and to benefit patients with irritable bowel syndrome, improving both constipation and diarrhea. Our aim was to define how psyllium modified the whole-gut transit of a radiolabeled lactulose-containing test meal by using gamma scintigraphy. Eight subjects participated in a randomized crossover study comparing gastric emptying and small bowel and colonic transit after consumption of 20 mL lactulose three times daily with or without 3.5 g psyllium three times daily. Psyllium significantly delayed gastric emptying: the time to 50% emptying increased from a control value of 69 +/- 9 to 87 +/- 11 min (mean +/- SEM; P < 0.05, n = 8). Small bowel transit was unaltered. However, progression through the colon was delayed with an increase in the percentage of the dose at 24 h in the ascending (control group: 2 +/- 3%, psyllium group: 11 +/- 8%; P < 0.02) and transverse colon (control group: 5 +/- 12%, psyllium group: 21 +/- 14%) with correspondingly less in the descending colon. Although the time for 50% of the isotope to reach the colon was not significantly different with psyllium, psyllium significantly delayed the rise in breath-hydrogen concentrations, which reached 50% of their peak at 217 +/- 34 min compared with control values of 155 +/- 27 min (P < 0.05). Psyllium delays gastric emptying, probably by increasing meal viscosity, and reduces the acceleration of colon transit, possibly by delaying the production of gaseous fermentation products.

Adult↗
PubMed1989

Dietary intake and colon cancer: sex- and anatomic site-specific associations.

A case-control study was conducted in Utah between July 1979 and June 1983 in which 231 cases of colon cancer identified through the Utah Cancer Registry and 391 controls identified through random digit dialing were interviewed. Odds ratios (OR) were calculated comparing the highest exposure categories with the lowest exposure categories. The highest quintile of body mass index (weight (kg)/height (m)2 for males; weight (kg)/height (m)1.5 for females) was associated with increased risk in both males (OR = 2.1) and females (OR = 2.3). In females, total dietary fat (OR = 1.9) and energy intake (OR = 1.5) were associated with an increased colon cancer risk after adjusting for age, body mass index, and crude fiber. Fiber was protective in females (OR = 0.5) after adjusting for age, body mass index, and energy intake, as was beta-carotene (OR = 0.5) after also adjusting for crude fiber. Adjusted risk estimates in males were 2.0 for total dietary fat, 3.8 for polyunsaturated fat, 2.1 for monounsaturated fat, 2.1 for energy intake, 2.5 for protein, 0.3 for fiber, 0.4 for beta-carotene, and 0.3 for cruciferous vegetables. Risk estimates differed by site of cancer within the colon. In males, protein (OR = 3.8) was a risk factor for cancer of the descending colon, while fats (OR = 2.7-8.8) increased the risk of cancer of the ascending colon. The hypotheses that dietary fat increases colon cancer risk while dietary fiber decreases colon cancer risk and that fat and protein may be independently associated with colon cancer risk are supported.

Aged↗
PubMed1996

Glassy cell carcinoma of the colon with human chorionic gonadotropin-production. A case report with immunohistochemical and ultrastructural analysis.

An unusual tumor in the descending colon with human chorionic gonadotropin-beta (HCG-beta) production and histological features of a "glassy cell" carcinoma is presented. Glassy cell carcinoma has been described in the uterus and fallopian tubes as well as the cervix, but in these locations the tumor is not HCG-beta producing. Glassy cell carcinomas have been described in some cases as having glandular and squamous differentiation as well as marked cellular pleomorphism. The tumors are generally associated with a poor prognosis.

Adult↗
PubMed1999

The effects of biofeedback on rectal sensation and distal colonic motility in patients with disorders of rectal evacuation: evidence of an inhibitory rectocolonic reflex in humans?

OBJECTIVE: Abnormalities of descending colon motility reported in a subset of patients with rectal evacuation disorders are consistent with a rectocolonic inhibitory reflex. Our aims were to evaluate distal colon motor function and rectal sensation in such patients and assess effects of biofeedback (BF) training on these functions. METHODS: Seven patients (five women, two men; mean age 36 yr) with rectal evacuation disorders were studied before and after 10-days biofeedback training; six healthy volunteers (five women, one man; mean age 30 yr) were studied once. Colonic compliance, motility, sensation thresholds, and perception scores during standardized rectal distentions were measured using two barostat-manometry assemblies inserted into the cleansed colon with the aid of flexible sigmoidoscopy. RESULTS: Sigmoid compliance, fasting, and postprandial motility index, and perception thresholds were similar in controls and patients before and after biofeedback training. Postprandial sigmoid tone tended (p = 0.09) to be lower in patients than controls; after biofeedback, postprandial tone was comparable to that in controls. Rectal urgency scores at 24 mm Hg distention were greater in patients than in controls (p = 0.02 for both). After biofeedback, there were trends for lower perceptions of urgency to defecate (7.6 +/- 1.1 cm pre- vs 5.3 +/- 1.5 post-; p = 0.04) at 24 mm Hg; conversely, gas sensation at 12 mm Hg was higher (1.2 +/- 0.5 cm pre- vs 3.3 +/- 0.6 post-; p = 0.05). CONCLUSIONS: Normalization of rectal evacuation and postprandial sigmoid tone in patients with evacuation disorders by biofeedback training supports the presence of a rectocolonic inhibitory reflex. Effect of biofeedback on rectal sensation in these patients requires further study.

Adult↗
PubMed1997

Effect of acute hyperglycemia on colorectal motor and sensory function in humans.

Increased use of laxatives and constipation are more common among people with diabetes mellitus than matched nondiabetic people in the same community. The mechanism of constipation in diabetes is unclear. Acute hyperglycemia was previously reported to reduce the gastrocolonic response. Our aim was to determine the effects of acute hyperglycemia on the colon compliance and motor response to feeding and on the sensory function of the colon and rectum in healthy human subjects. Eleven healthy individuals were studied under conditions of hyperglycemia (mean blood glucose 280 +/- 13 mg/dl) and euglycemia. We evaluated three parameters: 1) colonic motility and compliance by a multilumen manometry and barostatic balloon assembly in the descending colon (motility was studied during fasting and for 2 h postprandially); 2) perception of isobaric distensions of polyethylene balloons in the rectum and colon; and 3) rectal compliance. Initial tonic response to meal ingestion (0-5 min) was slightly lower during hyperglycemia (P = 0.3). However, colonic tone, motility, compliance, and sensation, as well as rectal compliance and sensation, were not significantly different under the conditions of euglycemia and acute hyperglycemia. In healthy individuals, acute hyperglycemia does not significantly change colonic or rectal motor functions or the perception of mechanosensory stimuli in the colon or rectum compared with euglycemia. These results do not support the hypothesis that hyperglycemia abolishes the colonic response to feeding.

Adult↗
PubMed1993

Colonic giant migrating contractions induced by glycerol enema in anesthetized rats.

Colonic motility was measured with three catheter pressure transducers that were inserted into the descending colon at the distance of 4 cm, 6 cm and 8 cm from the anal verge in anesthetized rats. Colonic infusion of glycerol (65%, 2 ml/kg) induced large phasic pressure changes with high amplitude and long duration. Some of the pressure changes propagated over all the three recording sites, appearing to be equivalent to giant migrating contractions. These glycerol-induced large propulsions were abolished by lidocaine (5%, 2 ml/kg, intracolon), hexamethonium (10 mg/kg, i.v.) or clonidine (30 micrograms/kg, i.v.); and they were almost entirely suppressed by atropine (3 mg/kg, i.v.), suggesting the principal involvement of the cholinergic neural pathway.

Animals↗
PubMed1991

A radiologic method for the study of postoperative colonic motility in humans.

Propulsive colonic motility in the postoperative period was studied, in 49 patients undergoing cholecystectomy, by means of radiopaque markers, water-soluble contrast, and serial abdominal radiographs. The colon was divided into four segments, and the propagation of the markers and contrast to the segments was registered. Marker propagation correlated significantly with the propagation of the contrast to all segments of the colon (p less than 0.001). The first postoperative passage of gas did not correlate significantly with the propagation of the markers or the contrast to the various colonic segments. The first passage of faeces postoperatively did not correlate significantly with the return of propulsive motility in the right colon; however, there was a significant correlation with the propulsion of markers to the descending colon (p less than 0.05) and the rectosigmoid colon (p less than 0.05). The duration of postoperative paralytic ileus, as measured by the start of propagation of the markers from the caecum, correlated directly with the consumption of opiate analgesics in the postoperative period (p less than 0.01) but inversely with age (p less than 0.05). The duration of surgery did not correlate significantly with the duration of paralytic ileus in the colon. In conclusion, a limited number of radiopaque markers can be used to study the return of postoperative propulsive motility in the colon. The first postoperative passage of gas is not an indicator of the duration of postoperative paralytic ileus, whereas the first passage of faeces is primarily representative of the return of propagative motility in the left colon.

Adult↗
PubMed1992

In vitro action of vasopressin on water absorption by rat colon.

The action of vasopressin on water absorption was studied in vitro in the colon of rats, weighing approximately 250 g. Everted sacs of intestinal segments (ascending and descending colons) prepared with mucosa only were used. Vasopressin (10 mM) significantly stimulated water absorption in both the proximal (4.85 +/- 3.78 vs 1.51 +/- 1.16 ml/mg) and distal (10.39 +/- 3.52 vs 7.22 +/- 3.58 ml/mg) colon, which corresponds to an increase of 220% and 50%, respectively. The results indicate the need for a study of the possible physiological function of vasopressin in enhancing intestinal water absorption, when it is released in response to plasma hyperosmolarity.

Animals↗
PubMed1989

[Atypical locations of tuberculosis of the colon].

We present four cases of tuberculosis of the colon in the form of multiple segmental lesions located in the ascendant, transverse and descendant colon. We comment on the rarity of these locations and how they are easily confused with other diseases, like adenocarcinoma or Crohn's disease. For a correct diagnosis, affectation of the cecum and terminal ileum is useful. In cases in which these zones are not involved, differentiation is very difficult and can only achieved by bacteriological and histological studies after colonoscopy and biopsy.

Adolescent↗
PubMed1984

Site-specific induction of nuclear anomalies (apoptotic bodies and micronuclei) by carcinogens in mice.

The usefulness of nuclear anomalies (NA) as a short-term test for indication of carcinogens in the mouse colon has been suggested previously by experiments in which colon-specific carcinogens induced NA in the colon, whereas non-colon carcinogens were, in general, impotent in that organ. We have extended this work to other sites in the digestive tract of female C57BL/6 mice treated with gamma-rays, 1,2-dimethylhydrazine dihydrochloride, or N-methylnitrosourea. Each agent induced NA at all of the sites examined. The frequency of NA at different times after treatment depended upon both the agent used and the site examined. 1,2-Dimethylhydrazine dihydrochloride (which is known to induce tumors predominantly in the colon) induces NA with the highest efficiency (relative to gamma-rays) in the descending colon. N-Methylnitrosourea (which induces tumors mainly in the forestomach) induces NA with the highest efficiency in the forestomach. These results further support the usefulness of the assay in that the frequency of NA produced at the various sites by 1,2-dimethylhydrazine dihydrochloride and N-methylnitrosourea correlates with that found in the carcinogenicity studies.

1,2-Dimethylhydrazine↗
PubMed1980

Epithelial blood group antigens in human carcinomas of the distal colon: further studies on their pathologic significance.

Blood group antigen content of human carcinomas located in the distal large bowel (descending colon, sigmoid colon, and rectum) was determined by the specific red cell adherence reaction and was compared to several morphologic features of prognostic significance, e.g., differentiation, extent of tumor spread, peritumoral lymphoplasmocytic infiltration, and growth patterns. About 50% of the carcinomas expressed blood group antigens in either diffuse or patchy distribution. Classification of tumors according to the extent of local spread revealed that 60% of Dukes stage A tumors were blood group antigen-negative, whereas 58% of those in Dukes stage B were positive. Dukes stage C lesions had an intermediate position, and this limits the prognostic usefulness of blood group antigen determinations. No significant correlations were found between blood group antigenicity and the degree of histologic differentiation, the degree of peritumoral lymphoplasmocytic infiltration, and the mode of tumor growth.

Adenocarcinoma↗
PubMed1980

The microbiology of transmissible murine colonic hyperplasia.

The relationship of Citrobacter freundii (4280) to the development of colonic hyperplasia in mice was investigated. The number of Citrobacter freundii (4280) in the descending colon were quantitated at intervals following experimental inoculation, and findings were correlated with previously reported histological and ultrastructural findings. Citrobacter freundii (4280) was a transient infection, lasting 2-3 weeks, after which time mice no longer harbored the organism. Neomycin sulfate and tetracycline hydrochloride, when administered in the drinking water, were useful in the prevention of infection as well as ablation of established infection. The presence of Citrobacter freundii (4280) for as little as 2 days was sufficient stimulus to result in detectable mucosal hyperplasia. The longer the bacterium was present, through 10 days, the greater the hyperplasia.

Animals↗
PubMed1986

[An autopsy case of Cronkhite-Canada syndrome developing after hemicolectomy for colonic cancer].

This is the patient previously reported as Cronkhite-Canada syndrome developing after left hemicolectomy for cancer of the descending colon. Ultimately, he died at the age of 62 of metastatic colonic cancer 8 years after the onset of the syndrome. In this paper, the findings of autopsy as well as the follow-up examination including the right hemicolectomy are presented, with particular emphasis on the histology of the polyps. The polyps of the stomach and colon were composed of cysticalydilated glands with inflamed and edematous stroma. In addition, most of the colonic polyps showed adenomatous foci at the surface, one of them being associated with focal severe atypia. This case supports the possibility of adenomatous to malignant transformation of the retention-type polyps, rather than the incidental occurrence of adenoma de novo in Cronkhite-Canada syndrome.

Alopecia↗
PubMed1983

Morphological observations on mucus-secreting nongoblet cells in the deep crypts of the rat ascending colon.

In the ascending colon of adult male rats, large accumulations of differentiated, mucous-type cells were observed which formed the deep one-half to one-third of the crypts almost exclusively. Mitotic activity was localized to the midcrypt, to columnar-type cells. The mucous-type cells were designated as "deep crypt secretory" (DCS), and their histological study was initiated. In the light microscope, the apical cytoplasm was distended with mucous vacuoles which stained differently from goblet cells after using periodic acid-Schiff (PAS), alcian blue, or a Masson stain. In electron-micrographs, a well-developed Golgi complex and rough edoplasmic reticulum in addition to a large number of electron-opaque vacuoles indicated active production of a glycoprotein. The midcrypt mitotic activity was further demonstrated by using the colchicine technique and 3H-thymidine radioautography. A gradual increase of mucus content and a decrease of nuclear and nucleolar size in the DCS cells from midcrypt to crypt base indicated that these cells originate in midcrypt and mature as they progress toward the crypt base. Cell counts showed that the number of cells constituting the crypts was about the same all along the colon, but the percentage of DCS cells varied: 33% in ascending and 21% in transverse colon. Only 5% and 8% deep-crypt mucous-type cells were found in descending colon and cecum, respectively; but these cells differed in appearance from the mature DCS cells. In conclusion, the presence of a large number of nonmitotic end cells with intense secretory activity has been ascertained for the deep crypts of the ascending colon. The exact relation of these cells to the vacuolated or other epithelial cell types remains for further study.

Animals↗