A rare case of haemorrhagic shock secondary to spontaneous rupture of a branch of the left colic artery and the right gastric artery.

Spontaneous splanchnic artery rupture is associated with up to 70% mortality. Affected vessels are often aneurysmal, secondary to atherosclerosis. We report, to our knowledge, the only case of spontaneous rupture of a branch of the left colic artery and the right gastric artery, possibly secondary to vasculitis.

Laparoscopic inguinal hernia repair: a rare case of colonic mesh migration.

Inguinal hernia repair can be performed via either an open or laparoscopic technique. Use of a mesh to repair the abdominal wall defect is now common practice, leading to a reduction in hernia recurrence but also associated with a number of complications. We report a rare case of a 49-year old man who presented 3 years after laparoscopic hernia repair with right-sided abdominal pain and loose stools. Colonoscopy and computed tomography revealed a mesh and fixation devices within the lumen of the caecum and ascending colon. The mesh was successfully excised with primary closure of the bowel defect. This case highlights the importance of recognising mesh migration as a complication of hernia repair, a phenomenon which can lead to serious morbidity. We suggest that patients should be informed of this risk during the consent process, while further research is needed to investigate how this occurrence can be prevented.

Management of left sided colorectal emergencies. Results of a postal questionnaire.

AIM: Controversy continues over management of left sided colorectal emergencies. Historically, management was by a three-staged procedure but more recently a two-staged procedure (Hartmann's) was adopted. Since Dudley's description of the safety of peroperative antegrade colonic irrigation and primary anastomosis (PA) in the 1980s, some surgeons have adopted this one staged procedure. Studies have reported good outcomes. However, uptake of a one-staged approach is by no means universal. The aim of this study was to establish the operative choices of surgeons for emergency left sided colonic pathologies. We also compared the operative choices of colorectal surgeons, with non-colorectal surgeons. METHODS: A paper questionnaire was sent out to 300 consultant surgeons, equally to colorectal and non-colorectal surgeons practising in UK. They were asked to state their specialist surgical interest and which operation they would perform for: obstructed sigmoid carcinoma; obstructed sigmoid colon due to diverticular stricture; perforated sigmoid carcinoma; diverticulitis and purulent peritonitis; perforated diverticulitis with faecal peritonitis. RESULTS: Of the 300 questionnaires sent out 145 (48%) were returned. Of these 72 (50%) were colorectal surgeons, 58 (40%) were non colorectal surgeons. For obstructed sigmoid carcinoma, obstruction due to diverticular stricture and purulent diverticulitis, colorectal surgeons were statistically more likely to perform PA than non-colorectal surgeons. CONCLUSION: Our study indicates that colorectal surgeons are more likely to perform a single stage operation for all scenarios examined. It also shows that the attitude of surgeons in UK is changing and more are accepting the concept of specialistic management in complex colonic pathologies.

The 5-HT4 receptor mediates 5-hydroxytryptamine-induced rise in short circuit current in the human jejunum in vitro.

BACKGROUND: 5-Hydroxytryptamine (5-HT) is a potent intestinal secretagogue for chloride and a mediator of diarrhea in the carcinoid syndrome. 5-HT-induced chloride secretion is seen as a change in short circuit current (Isc) in muscle-stripped, chambered human jejunum. The aim of this study was to determine which 5-HT receptors mediate a 5-HT-induced change in Isc in the human jejunum. METHODS: Segments of jejunum obtained from patients (n = 23) having obesity surgery were stripped of muscularis, and the mucosal sheets were mounted in flux chambers and short-circuited. By a cumulative method, a 5-HT-induced change in Isc was measured in the presence or absence of 0.2 mumol/L of neural conduction inhibitor tetrodotoxin or 5-HT receptor antagonists (n = 4 to 5): 10 mumol/L 5-HTP-DP, a 5-HT1p antagonist; 0.1 mumol/L ketanserin, a 5-HT2 antagonist; 0.3 mumol/L ondansetron, a 5-HT3 antagonist; 0.05 and 1 mumol/L ICS 205-930, a selective 5-HT3 antagonist at 0.05 mumol/L and also a 5-HT4 antagonist at 1 mumol/L or more; and 0.01 mumol/L GR 113808, a new selective 5-HT4 antagonist. A chloride-free solution or furosemide (100 mumol/L) was used to show the relationship of a 5-HT-induced change in Isc to chloride secretion. RESULTS: Data were analyzed by ANOVA; p < 0.05 was significant. The chloride-free solution and furosemide significantly (p < 0.05) depressed the maximum change in Isc. Significant shifts occurred in the median effective concentration (1.5 +/- 0.2 mumol/L) for 5-HT in the presence of 1 mumol/L ICS 205-930 (3 +/- 0.2) and 0.03 mumol/L GR 113808 (2.4 +/- 0.2), but not in the presence of 5-HTP-DP (1.2 +/- 0.4), methysergide (1.8 +/- 0.3), ketanserin (2.4 +/- 0.6), ondansetron (1.6 +/- 0.1), 0.05 micron ICS 205-930 (1.3 +/- 0.1), or tetrodotoxin (1.4 +/- 0.4). CONCLUSIONS: In the human jejunum in vitro, a 5-HT-induced change in Isc is mediated through a tetrodotoxin-insensitive pathway by the 5-HT4 receptor. Antagonists to this receptor may be useful in the treatment of diarrhea in carcinoid syndrome.

The role of the 5-HT4 receptor in Cl- secretion in human jejunal mucosa.

5-Hydroxytryptamine (5-HT) is a mediator of chloride ion (Cl-) secretion in the intestine which can be seen as a rise in short circuit current (Isc) in the Ussing chamber model. We investigated the 5-HT receptor mediating 5-HT-induced Cl- secretion in the human jejunum in vitro. Jejunal segments obtained from patients having gastric bypass surgery for obesity, were stripped of muscularis and mounted in Ussing chambers and short-circuited. The 5-HT receptor agonist-induced change (delta) in Isc was recorded in the presence and and absence of 5-HT receptor antagonists. The rank order of agonist potency was: 5-HT > 5-methoxytryptamine > renzapride (BRL 24924 > alpha-methyl-5-HT >> 2-methyl-5-HT. In the presence of Cl(-)-free media or 100 microM furosemide, 5-HT-induced delta Isc was significantly reduced. It was also antagonized by > or = 1 microM tropisetron (a 5-HT 3/5-HT4 receptor antagonist) and > or = 10 nM GR 113808 (a selective 5-HT4 receptor antagonist) with pA2 values of 6.5 and 7.9, respectively. Another 5-HT4 receptor antagonist, SC 53606 (0.1 microM), antagonized the 5-HT-induced response with a pA2 of 7.3 5-HT1-like/5-HT2 (methysergide), 5-HT1P [N-acetyl-5-hydroxytryptophyl 5-hydroxytryptophan amide (5-HT-DP], 5-HT2A (ketanserin) and 5-HT3 (ondansetron) receptor antagonists and tetrodotoxin, had no significant effect on the EC50 for 5-HT. In conclusion, this study demonstrates that in the human muscle-stripped jejunum in vitro, 5-HT induced change in short circuit current is mediated by a 5-HT4 receptor via a non-neural pathway.

5-Hydroxytryptamine-induced Cl- transport is mediated by 5-HT3 and 5-HT4 receptors in the rat distal colon.

In the rat distal colon, 5-hydroxytryptamine (5-HT)-induced Cl- secretion is seen as a rise in short circuit current (Isc). We investigated the 5-HT receptor mediating 5-HT-induced Cl- secretion in the rat distal colon. Rat distal colon was prepared either by stripping away the muscularis propria with the neural ganglia, or by leaving it intact. The tissue was mounted in Ussing chambers and short circuited. 5-HT receptor agonist-induced changes (delta) in Isc were recorded in the presence and absence of 5-HT receptor antagonists. In stripped preparations, the rank order of potency of agonists was: 5-HT > 5-methoxytryptamine > alpha-methyl-5-HT >> 2-methyl-5-HT. 5-HT and 5-methoxytryptamine-induced changes in Isc were antagonized by > or = 0.3 microM tropisetron with pA2 values 6.5 and 6.4, respectively. The 5-HT4 antagonist, SC 53606, antagonized the 5-HT-induced response with a pA2 of 7.2. 5-HT1-like (methysergide), 5-HT1P (N-acetyl-5-hydroxytryptophyl 5-hydroxytryptophan amide (5-HTP-DP)), 5-HT2A (ketanserin) and 5-HT3 (ondansetron) receptor antagonists had no significant effect on the 5-HT response in stripped tissue. 3 microM forskolin, or 10 microM 3-isobutyl-1-methyl-xanthine (IBMX), decreased the EC50 and increased the maximum 5-HT response. The 2-methyl-5-HT and 5-HT-induced delta Isc in the unstripped colon preparation were antagonized by the 5-HT3 antagonist, ondansetron (0.3 nM), and 2-methyl-5-HT activity was abolished by pretreatment with tetrodotoxin. In conclusion, 5-HT-induced delta Isc is neurally mediated via a 5-HT3 receptor, and non-neurally mediated via a 5-HT4 receptor in the rat distal colon.

Post vasectomy analysis: call for a uniform evidence-based protocol.

BACKGROUND: Vasectomy is a safe and reliable means of contraception that is used by 42 million couples world-wide. There are no standardised guidelines in the follow-up of these patients to assess the efficacy of the procedure, however. Through this paper we aim to recommend a guideline that is both clinically effective and cost effective, and would avoid medicolegal debate. PATIENTS AND METHODS: A questionnaire was sent to consultant general surgeons and urologists working both within and outside the North-West region, to assess the range of protocols used in the follow-up of patients undergoing vasectomy. RESULTS: Of respondents, 75% sent the vas deferens routinely for histology: 90.4% requested 2 sperm samples routinely whilst 4.8% requested 1 sample and 4.8% requested 3 samples. 95.2% requested further sperm samples if non-motile sperm were present. 98.8% performed their first sperm sample by 12 weeks. CONCLUSIONS: There is a wide range of protocols used in the follow-up of patients post-vasectomy. Most do not appear to be evidence-based. We recommend a guideline which re-emphasises the importance of pre-operative counselling, only 1 routine sperm sample taken 16 weeks post-vasectomy, and further samples taken only if motile sperm is seen. Non-motile sperm is not an indication for further sperm samples. We believe this guideline would be both clinically effective and cost effective.

Evidence for a 5-HT4 receptor pathway mediating chloride secretion in the rat distal colon.

Serotonin (5-HT) is a potent secretagogue of chloride ion (Cl-) and a mediator of diarrhea in the carcinoid syndrome. We investigated the role of the 5-HT4 receptor pathway in mediating 5-HT-induced Cl- secretion that is seen as a rise in short circuit current (Isc) in the Ussing chamber. Rat distal colon was stripped of the muscularis, mounted in Ussing chambers, and short circuited. By cumulative concentration responses, 5-HT-induced rise in Isc was measured in the presence and absence of 0.1 microM of the nerve conduction blocker, tetrodotoxin (TTX). TTX was later added routinely to remove any effects of residual nerve tissue. 5-HT concentration response was measured in the presence and absence of the following 5-HT receptor antagonists: 10 microM 5-HTP-DP (5-HT1p), 1 microM methysergide (5-HT1-like and 5-HT2), 0.1 microM ketanserin (5-HT2), 0.3 microM ondansetron (5-HT3) 0.1, 0.5, 1 and 3 microM ICS 205-930 (5-HT3 and 5-HT4), and 0.1, 0.03, and 0.01 microM of the new selective 5-HT4 antagonist, SC 53606. Data were analyzed by ANOVA. TTX had no effect on EC50 for 5-HT. ICS 205-930 and SC 53606 produced dextral shifts in 5-HT concentration-response curves and at all concentrations a significant shift in the EC50 for 5-HT, except at 0.1 microM ICS 205-930. The Schild plot slopes for ICS 205-930 (0.8) and SC 53606 (0.7) were not significantly different from unity. The pA2 values were 6.5 and 7.2, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Sickle cell trait and acute intermittent porphyria leading to small bowel infarction.

Sickle cell trait patients rarely have crises. A case of co-morbidity with acute intermittent porphyria is described in which trans-mural infarction of the distal ileum secondary to red cell sickling resulted in a fatal outcome.

A 5-HT3 receptor agonist induces neurally mediated chloride transport in rat distal colon.

Having previously demonstrated that serotonin (5-HT)-induced chloride secretion in rat distal colon is mediated at both neural and nonneural receptors, we isolated the neural component of this response by adding the selective 5-HT3 receptor agonist, 2-methyl-5-hydroxytryptamine (2Me5HT), to in vitro sheets of rat distal colon with intact neural plexuses. Rats were sacrificed, and the distal colon excised, opened, cut into sections and mounted, all layers intact, as flat sheets in Ussing chambers under short-circuited conditions. 2Me5HT induced a prompt, significant (P < 0.01), concentration-dependent rise in short-circuit current (Isc; EC50 6.2 microM); 50 microM 2Me5HT decreased both net sodium and chloride absorption (-0.1 +/- 0.5 and -2.1 +/- 0.8 muEq/cm2 x hr, respectively); the difference (2.0 +/- 0.8 muEq/cm2 x hr) in these changes was not statistically different from the rise in Isc (1.5 +/- 0.3 muEq/cm2 x hr). Since the only significant change in unidirectional flux was the rise in electrogenic Cl- secretion (P < 0.01), the delta Isc induced by 2Me5HT may be used as a measure of electrogenic chloride secretion induced by the agonist. The rise in Isc induced by 2Me5HT was abolished by both 0.2 microM tetrodotoxin and 0.1 microM ICS 205-930 (a 5-HT3 antagonist) but was not inhibited by 1.0 M atropine 100 microM hexamethonium, 10 microM phentolamine, 10 microM propranolol, 10 microM 5-HTP-DP (a 5-HT1P antagonist), or 0.1 microM ketanserin (a 5-HT2 antagonist). These results indicate that 2-methyl-5-HT is a highly selective agonist for neurally based 5-HT3 receptors in this model.(ABSTRACT TRUNCATED AT 250 WORDS)

Serotonin induces Cl- secretion in human jejunal mucosa in vitro via a nonneural pathway at a 5-HT4 receptor.

We examined the effect of 5-hydroxytryptamine (5-HT) on Na+ and Cl- flux (J) and short-circuit current (Isc) in human jejunal mucosa. Segments of jejunum, taken at the time of gastric bypass surgery, were stripped of the seromuscular layers (and attached neural ganglia) and mounted as flat mucosal sheets in Ussing chambers under short-circuit conditions. 5-HT (0.1-100 microM) produced a concentration-dependent rise in Isc (mean effective concn = 2.5 microM). Using 22Na and 36Cl, we measured flux across control tissues and in those exposed to 5-HT. 5-HT decreased both net JNa and JCl and increased Isc (-1.1 +/- 0.6, -1.7 +/- 0.6, and 0.6 +/- 0.1 mueq.cm-2.h-1, respectively). Thus the 5-HT-induced rise in Isc could be accounted for by reduced net JNa and JCl. 5-HT induced a significant (P < 0.05) Cl- secretion (serosal-to-mucosal flux) when glucose was included in the buffer bathing the mucosal surface. Neither tetrodotoxin, the adrenergic receptor antagonists prazosin and propranolol, nor the cholinergic receptor antagonists atropine and hexamethonium inhibited the change (delta) in Isc induced by 5-HT. 5-Methoxytryptamine (5-MeOT) and zacopride, known 5-HT4 receptor agonists, induced significant delta Isc. The 5-HT receptor antagonists N-acetyl-5-hydroxytryptophyl-5-hydroxytryptamine (5-HT1P), ketanserin (5-HT2), and ICS-205-930 (preferential for 5-HT3 at 0.1 microM had no effect on delta Isc.(ABSTRACT TRUNCATED AT 250 WORDS)