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PubMed1987

The effect of angiotensin II upon electrogenic ion transport in rat intestinal epithelia.

Epithelial sheets from rat jejunum and descending colon have been shown to respond to angiotensin II (AII) when studied under short-circuit conditions and bathed on both sides with Krebs-Henseleit solution. The octapeptide AII elicited increases in short-circuit current (SCC) in preparations of jejunum and decreases in SCC in the descending colon; both responses occurred when the peptide was applied to the basolateral surface, but not when applied to the apical solution. Responses in both tissues were highly specific, being inhibited by a range of AII antagonists with the following order of potency: [Sar1. Thr8]-AII greater than [Sar1. Leu8]-AII greater than [Sar1. Ile8]-AII greater than [Sar1. Ala8]-AII greater than [Des,Asp1. Ile8]-AII in rat jejunum. AII responses were not affected by alpha- or beta- adrenoceptor antagonists, atropine or tetrodotoxin. AII responses were totally inhibited by the chloride channel blocker, diphenylamine-2-carboxylate (DPC) while cotransport inhibitors e.g. piretanide and frusemide significantly reduced the size of AII responses in colon and jejunum. These patterns of activity suggest that in the jejunum the responses result from electrogenic chloride secretion. Although AII responses in colon were sensitive to DPC the transporting ions have not yet been identified. Both piroxicam and indomethacin inhibited the increase in SCC elicited by AII in the jejunum, and the reduction in SCC caused by AII in the colon. Taken together these results indicate that eicosanoids are involved in AII responses in both tissues. This is the first study to demonstrate a direct, electrogenic effect for AII on transporting epithelia from the gastrointestinal tract. The responses are most probably initiated by All interacting with previously identified specific All receptors within the epithelial membranes.

Angiotensin I↗
PubMed1995

Colonoscopy: how far is enough?

Total colonoscopy is arguably the best method available for examination of the colon and rectum. Colonoscopy costs are high and rising and it may be that in the future practitioners will be unable to afford to colonoscope all of the patients presently being examined. This retrospective study was undertaken in an attempt to examine the cost, in terms of lesions missed, of a limited endoscopy programme. During a 15 year period, 1426 colonoscopies were performed at Wellington Hospital, New Zealand. Total colonoscopy was possible in 79% of all patients. Three perforations occurred. Nine patients bled and two required blood transfusion after biopsy or 'snaring' of polyps. After exclusion of patients with continuous inflammatory bowel disease (IBD) 75% of all lesions were found in or distal to the descending colon. More cancers were found in patients colonoscoped because of bleeding. Thirty-two of 93 cancers diagnosed were proximal to the descending colon but 18 presented with bleeding. A further seven had a radiological abnormality. Only 7.5% of colorectal cancers would be missed by flexible sigmoidoscopy (65 cm) and 75% of the costs of total colonoscopy would be avoided if only patients presenting with bleeding and IBD were offered total colonoscopy and patients with radiological abnormalities were treated according to the abnormality. This compromise, based on the data presented, may represent a rational way to reduce colonoscopy costs.

Colonic Neoplasms↗
PubMed1999

Rectal and colonic mesalazine concentration in ulcerative colitis: oral vs. oral plus topical treatment.

AIM: To measure mucosal concentrations of mesalazine in ulcerative colitis patients treated with oral mesalazine alone, compared to patients treated with both topical and oral mesalazine. METHODS: Twenty-two patients with mild to moderate ulcerative colitis were randomized to receive 2.4 g/day of oral mesalazine (11 patients) or 2.4 g/day oral plus 4 g/day of topical mesalazine (11 patients). After 2 weeks of treatment, endoscopic biopsies specimens were taken from the rectum and in descending colon just distal of the splenic flexure and stored to -80 degrees C for later assay (HPLC). Wilcoxon's rank sum test for unpaired data was used for the statistical analysis. RESULTS: Mucosal levels of mesalazine in the rectum were significantly higher in patients who received oral plus topical treatment than in those who had oral treatment alone (52.1 ng/mg, range: 13.6-122.1 vs. 0.2 ng/mg, range: 0.2-9.7, respectively; P < 0.0001). Similarly, in the descending colon, the mucosal concentrations of mesalazine were significantly higher in patients who had oral plus topical treatment than in those receiving oral treatment alone (46.6 ng/mg, range: 6-112.6 vs. 15.9 ng/mg, range: 2.3-42.4, respectively; P=0.01). CONCLUSIONS: Topical treatment of mesalazine significantly increases mucosal concentrations of mesalazine up to the splenic flexure, supporting the rationale to treat left-sided ulcerative colitis with topical formulations of mesalazine.

Administration, Oral↗
PubMed1985

[A case of renal cell carcinoma found in traumatic ruptured kidney].

A case of traumatic kidney rupture with pre-existing renal cell carcinoma in a 38-year-old male is reported. Macrohematuria appeared 48 hours after left precordial trauma in a traffic accident. Initial diagnosis at the emergency clinic was 9th rib fracture of his left chest alone and no other injury was recorded. A large mass in left abdomen was palpable at urologic OPD, however, and X-ray examination revealed a non-visualizing left kidney in IVP. After the ECHO, CT and arteriography findings gave an impression of left kidney rupture. Left nephrectomy accompanied by partial colectomy of descending colon by transperitoneal approach was performed 25 days after initial trauma. This delay was mainly due to disagreement of patient for surgical treatment because there were no subjective symptom except microhematuria and subsiding fever after transfer to the urologic section. En bloc removed specimen showed ruptured kidney with adhesiveness laterally to descending colon and harder core portion was found in midst of renal mass. Coronal slice of the specimen exhibited a renal parenchymal tumor with necrotic spots. Pathologic findings were complete kidney rupture in upper pole and clear cell type renal cell tumor was found in mid and lower pole. Also lymph nodes which obtained from left renal pedicle and para aortic margin proved no metastasis of tumor cell. Post operative clinical course was favourable without any recurrence for 15 months after surgery. Clinical incidence of type I and type II kidney trauma with pre-existing neoplastic change is considerably high, but the kidney ruptured case bearing renal cell carcinoma as a core shape is very rare.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1979

Cyclic adenosine 3', 5' monophosphate: a possible indicator of premalignant changes in the large bowel.

Cyclic adenosine 3', 5' monophosphate (cyclic-AMP) has been estimated in mucosal biopsy samples removed from the descending colon and rectum at endoscopy to investigate the possibility of using this substance for monitoring pre-malignant changes in the large bowel. Four groups of patients have been studied: those with normal large bowel and rectal mucosa; those with non-malignant inflammatory bowel disease; those with an adenomatous polyp in the descending colon or sigmoid colon; and those with a rectal adenocarcinoma. No difference was found in the cyclic-AMP content of 'normal' rectal mucosa, 'normal' colonic mucosa, 'diseased' colonic mucosa, carcinomas, and uninvolved mucosa adjacent to the polyps. Less cyclic-AMP was found in the polyps than in adjacent uninvolved mucosa. Conversely, more cyclic-AMP was found in the carcinomas than in adjacent uninvolved mucosa. It is concluded that although cyclic-AMP may be a very useful parameter for delineating the extent of the disease in individual patients, it is not a suitable biochemical marker for the screening of neoplastic changes in the large bowel in the population as a whole.

Colonic Neoplasms↗
PubMed2000

Coloanal motor coordination in association with high-amplitude colonic contractions after pharmacological stimulation.

OBJECTIVE: The rectoanal inhibitory reflex facilitates defecation by relaxation of the internal anal sphincter during rectal distention by gas or stool. Defecation is sometimes preceded by high-amplitude propagated contractions (HAPCs). Our objective was to seek evidence for motor coordination between human colonic and anal sphincter functions. METHODS: As part of a study of alpha2 modulation of colonic and anal motor functions in 32 healthy volunteers, we studied the relationship between high HAPCs and anal sphincter pressure with colonic manometry, barostat, and a Dent sleeve in the anal canal. RESULTS: Twenty-two HAPCs were observed; in 19/22 HAPCs there was optimal positioning of the Dent sleeve to assess the anal sphincter. Eighteen of 19 HAPCs occurred postprandially; 14 HAPCs occurred after administration of yohimbine, three after clonidine, and one before any drug administration. Seven followed experimental balloon distention. Anal sphincter relaxation occurred (14 +/- 4 s) before the recorded onset of HAPC in the descending colon and 88 +/- 7 s before the arrival of the HAPC in the rectum. After or during the HAPCs, anal sphincter pressure decreased by 40 +/- 4% and increased by 56 +/- 8% in the postrelaxation phase. CONCLUSIONS: The close temporal association between anal sphincter relaxation and onset of HAPC in the descending colon suggests a coloanal reflex that may facilitate defecation during mass movements independently of the rectoanal inhibitory reflex.

Adrenergic alpha-Agonists↗
PubMedDate not supplied

Surgical approaches to obtaining optimal bowel function.

Approximately 50% of patients have an unsatisfactory functional result after traditional restorative rectal resection, and an even higher percentage, at least in the early postoperative period, suffers from urgency, frequent bowel movements, and occasional faecal incontinence. The rectal reservoir function is disturbed after restorative surgery. This is related to the size of the rectal remnant, the viscero-elastic properties, and the motility pattern of the neorectal wall, because segments of the remaining colon can only substitute for the rectum to a limited extent. A straight anastomosis is recommended when the rectal remnant (measured from the anal verge) is at least 7 to 8 cm. The side-to-end anastomosis is probably preferable to the end-to-end anastomosis. In contrast, a straight anastomosis at the levator plane cannot be recommended. If straight anastomosis is still considered, the descending colon should be used rather than the sigmoid colon. The colonic pouch was introduced to increase the neorectal volume and eliminate some of the functional disturbance associated with the reduced neorectal volume occurring after a straight colo-anal anastomosis. To obtain optimal functional results soon after surgery, a pouch should be used when the anastomosis is located 3 to 5 cm from the anal verge. The size of the pouch should not be too small. A staple line of 6 to 7 cm is a fair compromise between the low anterior resection syndrome and problems with evacuation. Since the descending colon has a thinner wall and often is healthier than the sigmoid colon, it should be the first choice for the anastomosis.

Anal Canal↗
PubMed2006

Colostomy in anorectal malformations: a procedure with serious but preventable complications.

PURPOSE: Colostomy for patients with anorectal malformations decompresses an obstructed colon, avoids fecal contamination of the urinary tract, and protects a future perineal operation. The procedure is associated with several significant complications. MATERIALS AND METHODS: The medical records of 1700 cases of anorectal malformations were retrospectively reviewed. A total of 230 patients underwent reconstruction without a colostomy. Of the remaining 1470 patients, 1420 had their colostomy performed at another institution (group A) and 50 did at our institution (group B) using a specific technique with separated stomas in the descending colon. RESULTS: There were 616 complications identified in 464 patients of group A and in 4 patients in group B, an incidence of 33% vs 8% (P < .01). Complications in group A were classified into several groups. The first group was mislocation (282 cases), including 116 with stomas too close to each other, 97 with stomas located too distally in the rectosigmoid (which interfered with the pull-through), 30 with inverted stomas, 21 with stomas too far apart from each other, and 18 with right upper sigmoidostomies. The second largest group was prolapse (119 cases), which occurred mainly in mobile portions of the colon. The third group was composed of general surgical complications after colostomy closure (82 cases), such as intestinal obstruction (47 cases), wound infection (13 cases), incisional hernia (11 cases), anastomotic dehiscence (7 cases), sepsis (3 cases), and bleeding (1 case). Two of the septic patients died. Another group included 62 patients who received a Hartmann's procedure, which we considered to be contraindicated in anorectal malformations. A total of 42 patients suffered from stenosis of the stoma; 29, from retraction. CONCLUSIONS: Most colostomy complications are preventable using separated stomas in the descending colon. Mislocated stomas lead to problems with appliance application, interference with the pull-through, megasigmoid, distal fecal impaction, and urinary tract infections. Loop colostomies lead to urinary tract infections, distal fecal impaction, and prolapse. Prolapse is a potentially dangerous complication that mostly occurs when the stoma is placed in a mobile portion of the colon. Recognizing this makes the complication preventable by trying to create colostomies in fixed portions of the colon or by fixing the bowel to the abdominal wall when necessary. The trend to avoid colostomies is justified; however, colostomy is the best way to prevent complications in anorectal surgery and, when indicated, should be done with a meticulous technique following strict rules to avoid complications.

Abnormalities, Multiple↗
PubMed1986

Identification of selective, high affinity [125I]-angiotensin and [125I]-bradykinin binding sites in rat intestinal epithelia.

Specific [125I]-angiotensin II (AII) and [125I]-bradykinin (Bk) binding sites have been identified within epithelial membranes from rat jejunum and descending colon. These high affinity intestinal sites exhibited KD values of 0.64 +/- 0.16 nM for [125I]-AII and 0.69 +/- 0.13 nM for [125I]-Bk, which were similar to those for [125I]-AII (0.85 nM) and [125I]-Bk binding sites (1.03 nM) previously identified in renal cortex epithelia. Specific [125I]-AII binding capacity was only 19.77 +/- 2.74 fmol mg-1 in small intestine and 11.31 +/- 2.66 fmol mg-1 in descending colon epithelia while a larger population, 332.0 +/- 72.9 fmol-mg-1 of specific [125I]-Bk sites were identified in epithelial membranes from small intestine. Significant hydrolysis of both free [125I]-AII and [125I]-Bk was observed while membrane bound peptides remained relatively resistant to degradation. Whilst no corrections have been made to the observed values of KD and Bmax quoted above, one may assume that the calculated reductions in the free hormone concentration will result in a decrease of the KD value for both peptides. Loss of membrane bound peptide, particularly of [125I]-AII, may indicate that the calculated Bmax value is an underestimation. Despite the rapid degradation of unbound [125I]-AII and [125I]-Bk during incubations the kinetics of specific peptide binding were reversible and highly selective. The order of potency for specific [125I]-AII binding was [Sar1, Leu8]-AII greater than or equal to [Sar1, Thr8]-AII greater than or equal to AII greater than [Sar1, Ile8]-AII greater than or equal to [Des, Asp1, Ile8] AII greater than AIII. Specific [125I]-Bk binding was also highly selective, the order of potency being Phe8-Bk greater than or equal to Tyr8-Bk greater than or equal to Lys-Bk much greater than Des, Arg1-Bk. AII exhibited an IC50 of greater than 1mM for specific [125I]-Bk binding and likewise Phe8-Bk for specific [125I]-AII binding.

Angiotensin II↗
PubMed2006

Laparoscopic obliteration of the nephrosplenic space using polypropylene mesh in five horses.

OBJECTIVE: To report a laparoscopic technique for insertion of polypropylene mesh in the nephrosplenic space in horses and evaluate outcome. STUDY DESIGN: Descriptive experimental study. ANIMALS: Five healthy mature horses. METHODS: One laparoscope and 2 instrument portals were made on the left side of the horse. The nephrosplenic space was measured and appropriately sized polypropylene mesh was inserted and attached to the dorsolateral splenic capsule and perirenal fascia using helical titanium coils. All horses had repeat laparoscopy 4 weeks later and were necropsied at intervals 4-14 weeks after mesh placement. RESULTS: Mean time for laparoscopic mesh placement was 104 minutes. None of the horses had signs of colic and at 4 weeks all mesh implants were covered by fibrous tissue. One horse had a descending colon mesenteric adhesion to the mesh. At necropsy, the fibrous tissue covering the mesh had adhered to itself and pulled the splenic capsule and perirenal fascia into close apposition. Each mesh implant was firmly adhered to the spleen, nephrosplenic ligament, and perirenal fascia. CONCLUSIONS: Laparoscopic mesh placement was easily performed, well tolerated, and provided excellent fibrous obliteration of the nephrosplenic space. The single important complication observed was a mesenteric adhesion of the descending colon to the mesh in 1 horse. CLINICAL RELEVANCE: Laparoscopic placement of polypropylene mesh leads to obliteration of the nephrosplenic space within 4 weeks and should prevent entrapment of viscera in the nephrosplenic space.

Animals↗
PubMed1995

High tie of the inferior mesenteric artery in distal colorectal resections--a safe vascular procedure.

Division of the inferior mesenteric artery flush with the aorta (high tie) allows a tension-free anastomosis in distal colorectal resections but may also diminish the blood supply. Tissue oxygen tension was measured proximal to the resection margin before and after either low or high division of the inferior mesenteric artery in 62 patients undergoing elective colorectal resections. Oxygenation was maintained or improved when the transverse (median change after vs before resection for low tie +9 mmHg (P < 0.05), high tie +8 mmHg (P = 0.3)) and descending colon (low tie +7 mmHg (p < 0.01), high tie +1 mmHg (p = 0.67)) were used for the anastomosis but diminished for sigmoid anastomoses (low tie -4 mmHg (P = 0.42), high tie -9 mmHg (P < 0.05)). Change in oxygenation was significantly affected by location of proximal resection site but not by choice of high or low tie. These results suggest that the marginal artery provides a more than adequate vascular supply to the transverse and descending colon, but that the sigmoid colon is not suitable for anastomosis. We conclude that the sigmoid colon be sacrificed and there should be no hesitation in performing a high tie to avoid tension in low pelvic anastomoses.

Aged↗
PubMed2001

Evidence of local eosinophil activation and altered mucosal permeability in collagenous colitis.

The local release of the inflammatory mediators eosinophil cationic protein and myeloperoxidase and the permeability marker albumin was studied in collagenous colitis using a new technique for segmental perfusion of the rectum and descending colon. Perfusion of both segments was successful in 19/25 (76%) of patients with collagenous colitis and controls with noninflammatory conditions. The concentration of myeloperoxidase was increased in the perfusion fluids from both segments in only one patient with collagenous colitis and in none of the controls. On the other hand, concentrations of eosinophil cationic protein and albumin in the perfusate from the rectum were significantly increased in collagenous colitis compared with controls, and similar trends were seen in the perfusates from the descending colon. Furthermore, there was a significant correlation between the increased concentrations of eosinophil cationic protein and albumin, indicating a possible relation between eosinophil activation and disturbed mucosal permeability in collagenous colitis.

Adult↗
PubMed2001

Barostat examination of proximal site of the anastomosis in patients with rectal cancer after low anterior resection.

Patients who have undergone low anterior resection (LAR) of the rectum for cancer show symptoms of urgency and frequency of defecation after meals. The cause of these symptoms is unclear. It was hypothesized that the functional disorder of the proximal site of the anastomosis after low anterior resection of the rectum often leads to the symptoms and that the 5-HT3 receptor antagonist reduces postprandial colonic contractions. The aim of this study was to assess colon contractions of the proximal site of the anastomosis and the effects of the 5-HT3 receptor antagonist on the contractions. We evaluated 37 patients who had undergone LARs, 17 with high stool frequency (more than four times per day) and 20 with normal stool frequency. In the first part of the study, basal tone, compliance of the proximal site of the anastomosis, and response to a meal (300 kcal) were recorded with a barostat in all patients. In the second part of the study the effects of the 5-HT3 receptor antagonist on contractions of the proximal site of the anastomosis after ingesting a meal was evaluated. Seven healthy controls were also studied for descending colonic tone with a barostat after a meal. Basal barostat balloon volumes showed only small variations in the two post-LAR groups. Compliance of the proximal site of the anastomosis was similar in the two groups. Meal ingestion stimulated contractions of the proximal site of the anastomosis. In patients with high stool frequency the proximal site of the anastomosis contracted earlier than in those with normal stool frequency after a meal. The descending colonic tone of healthy controls did not change after a meal. The 5-HT3 receptor antagonist inhibited postprandial contractions of the proximal site of the anastomosis after LAR. These observations lend support to the idea that gastrocolonic reflex increases in patients who have undergone LAR, leading to high stool frequency. Furthermore, the 5-HT3 receptor antagonist may alleviate the symptoms of urgency and the frequency of defecation.

Adult↗
PubMed1989

Diphallia in a mixed-breed dog with multiple anomalies.

Complete diphallia was detected in a six-month-old Poodle cross dog. Duplication of the urinary bladder, right renal hypoplasia, bifurcation of the descending colon and bilateral cryptorchidism were also present. The left urethra was patent, and emptied the left urinary bladder; the right urethra ended blindly at a point 2.5 cm from the tip of the right penis. The left urinary bladder was joined medially to a right urinary bladder with no interbladder communication; however, the right bladder opened caudally into a blind sac which drained into the left prostatic urethra. Pyelonephritis of the left kidney was present, and was suspected to be due to ascending bacterial infection of the right urinary bladder and the right segment of the bifurcated descending colon, which terminated at the apex of the right urinary bladder. Diphallia and associated urogenital anomalies are reviewed.

Journal Article↗
PubMed2003

[Treatment of malignant colorectal obstruction by means of endoscopic insertion of self-expandable metallic stents].

BACKGROUND AND AIM: Self-expandable metallic stents are being used increasingly to treat the obstruction of different segments of the digestive tract and biliary tree. We present our centre experience on the initial resolution of malignant colorectal obstruction by means of this type of stents. PATIENTS AND METHODS: During a 18-month period, 13 patients patients suffering from malignant obstruction at the level of rectum, sigmoid or descending colon tried to be initially treated by means of endoscopic insertion of stents (non covered enteral Wallstents). Ten procedures were performed with both endoscopy and fluroscopy and three with only endoscopy. RESULTS: In 12 of the 13 patients (92,3%) the obstruction was solved by means of correct stent insertion. All the exclusively endoscopic procedures (without fluoroscopy) were successful. Six (50 %) patients with tumours at the rectosigmoid underwent later scheduled surgery. In the remaining six ones (a patient with an ovarian carcinoma and five with colonic adenocarcinoma) the stents were considered to be a palliative definitive treatment. Stent migration was observed in two of these patients and both were extracted endoscopically. Only one patient needed to have another stent inserted. A tumoural colo-vesical fistula developed in another patient in the palliative group, inside the previous inserted stent, and was treated by coaxial insertion of an esophageal Ultraflex. There were no other complications or mortality related to the endoscopic procedures. CONCLUSIONS: Self-expandable metallic stents might be considered, in general, as the initial treatment for the malignant obstruction at the level of rectum, sigmoid and descending colon

Adult↗
PubMed1996

Sex differences in time trends of colorectal cancer in England and Wales: the possible effect of female hormonal factors.

Differences between the sexes in time trends of colorectal cancer incidence 1962-87 and mortality 1960-91 in England and Wales are examined in relation to changes in female hormonal factors. There was a trend in the sex ratio of this tumour, particularly marked for the descending colon, whereby the female excess in risk at young ages has almost disappeared but the male excess at older ages has increased. This trend started for cohorts born since the 1920s and coincided with the increase in the use of oral contraceptives and, to a lesser extent, with increases in fertility. The decline has been particularly pronounced for women at young ages born since 1935-39, coinciding with the spread of oral contraceptive use to younger age groups. These results are consistent with the hypothesis that female hormonal factors may play a role in the aetiology of colorectal cancer and with the possibility that oral contraceptive use might exert a protective effect in the descending colon.

Adolescent↗
PubMed1983

Effects of trifluoperazine, ouabain, and ethacrynic acid on intestinal calcium transport.

Bidirectional steady-state calcium fluxes were measured in vitro under short-circuited conditions in segments of rat duodenum and descending colon. The calcium-activated ATPase (Ca-ATPase) inhibitor trifluoperazine (TFP, 0.1 mM) reduced net calcium absorption in both tissues by decreasing the absorptive flux from mucosa to serosa (Jm leads to s) without consistently altering the secretory flux from serosa to mucosa. 1,25-Dihydroxyvitamin D3 administration (50 ng/day for 4 days) increased net calcium absorption by increasing Jm leads to s, and TFP reduced Jm leads to s to the same extent across tissues from vehicle- or 1,25-dihydroxyvitamin D3-treated animals. Na-K-ATPase inhibitors ouabain and ethacrynic acid both reduced short-circuit current without affecting calcium fluxes. These data suggest that Ca-ATPase, located in the basolateral membrane of intestinal epithelial cells, plays a role in the transepithelial transport of calcium. More general effects of TFP on intestinal epithelium may also contribute to the reduction in calcium fluxes. Duodenal and descending colon calcium transport appears independent of transcellular sodium transport mediated by Na-K-ATPase.

Animals↗
PubMed1994

Patients with adenomatous polyps and carcinomas have increased colonic mucosal prostaglandin E2.

Colorectal carcinoma in humans and animal models is associated with increased synthesis of prostaglandin E2 (PGE2). PGE2 synthesis was measured in normal and neoplastic human colorectal mucosa to investigate its role in the adenoma-carcinoma sequence. Paired mucosal biopsy specimens for PGE2 synthesis and histological examination were obtained during 39 diagnostic colonoscopies. Twelve control patients in whom colonoscopies and histology were normal synthesised similar amounts of PGE2 at all sites. Their results were (mean (SD) pg PGE2/mg tissue) caecum 102.8 (15.9) (n = 6), ascending colon 110.8 (24.3) (n = 10), transverse colon 103.9 (19.5) (n = 11), descending colon 102.9 (23.2) (n = 12), sigmoid colon 96.4 (18.0) (n = 12), and rectum 107.1 (17.6) (n = 12). Nineteen patients had a total of 27 adenomatous polyps (rectum (1), sigmoid (22), descending (1), transverse (1), and ascending colon (1): histology-tubular (16), tubulo-villous (8), and villous adenomous (3)). The polyps (178.0 (55.0), n = 27) synthesised more PGE2 than controls (p < 0.001), but the values in polyp-associated mucosa (mean (SD) 115.4 (21.9), n = 15) were not different to control results. Eight patients had carcinomas (rectal (2), sigmoid (4), and caecal (2)) all of which were adenocarcinomas. The cancers (193.6 (40.2), n = 8) synthesised more PGE2 than control specimens (p < 0.001), but were not different to polyps. Cancer-associated mucosa (140.3 (27.7) n = 8) synthesised more PGE2 than control and polyp-associated mucosa. Colorectal neoplasia is associated with a progressive increase in PGE2 synthesis which may have a role in tumourigenesis and be a pathophysiological explanation for the beneficial effects of NSAIDs in animal models and human disease.

Adenocarcinoma↗