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J Kewenter

Publications and source records attributed to J Kewenter.

At least 73 records · Page 4Linked to original sources

The effect of parietal cell vagotomy and selective vagotomy with pyloroplasty on gastric emptying of a solid meal. A prospective randomized study.

A new technique is described whereby gastric emptying of a 51Cr-labelled solid meal (hamburger, vegetables, potatoes) was measured by way of a movable NaJ(T1) detector. The technique allowed separate measurements over the proximal and the distal part of the stomach. Seven volunteers took part in a study which revealed good correlation between two individual consecutive tests. Eight patients who took part in a controlled randomized series of parietal cell vagotomy (PCV) versus total gastric selective vagotomy and pyloroplasty (SV+P) underwent the test preoperatively and 6 to 8 months postoperatively. Following both operations gastric emptying was retarded. The time taken for the amount of meal remaining in the stomach to be reduced to 75,50 and 25% respectively was significantly longer postoperatively than before surgery, but there were no differences in this respect between PCV and SV+P. The retardation of gastric emptying of solids was in contrast to the emptying of 10% glucose solution, which in the same series of patients was found to be accelerated. Following PCV there was a change in the distribution of the meal within the stomach immediately after the intake of the meal: a larger part of the meal was found in the proximal stomach post-operatively than before operation. There was no significant change in this intragastric distribution of the meal after SV+P.

Adult↗

Gastric emptying of a liquid meal in health and duodenal ulcer disease.

In the present investigation an extension of the method of George was used, which allows the rate of emptying of the gastric content (GC) to be assessed. The aim of the study was to find out whether ther is any difference in gastric emptying rate of a liquid meal of 750 ml 10% glucose (glucose monohydrate, mol. wt. 198) between healthy subjects and duodenal ulcer patients (DU). The straight numerical volume of GC, the logarithm and the square root of GC were related to time, and these functions were compared. The correlation coefficient for the regression line for these functions showed that data both for healthy subjects and DU gave a better fit to the GC/time and GC/relationship than to a semi-logarithmic function, when the starting point at time zero was excluded. Regardless of the type of transformation of the basic data, there was no difference between healthy controls and DU as regards the regression coefficient, indicating that from 20 min after the installation of the test volume the GC is decreasing at the same rate in the two groups. When the straight numerical volume of GC was used, there was a significant difference in the extrapolated Y-intercept for the regression lines between healthy subjects and the DU, indicating an increased initial emptying in the DU patients. This was further confirmed when the volume emptied during consecutive 20-min periods was estimated. Furthermore, there was a shorter emptying time in patients with duodenal ulcer than in healthy controls.

Adult↗

Clinical results of parietal cell vagotomy and selective vagotomy with pyloroplasty in the treatment of duodenal ulcer. Two-year follow-up of a prospective randomized study.

Fifty patients were randomized in a consecutive series of parietal cell vagotomy (PCV) and selective vagotomy with pyloroplasty (SV +P) in the treatment of duodenal ulcer. There were no operative deaths, and the length of the hospital stay and time off from work were the same in both groups. The clinical results were evaluated at 1 and 2 years after operation. Within the first 3 years there were two recurrences after PCV and three after SV +P. The overall clinical result 2 years after surgery did not significantly differ between the two groups; 16/24 after PCV and 17/23 after SV +P classified as excellent results (Visick I). Significantly fewer patients had dumping after PCV (3/23) than after SV +P (13/22). No patient had diarrhoea postoperatively. It is concluded that parietal cell vagotomy gives less dumping than selective vagotomy with pyloroplasty. It is, however, too early to say whether the overall clinical result in a long-term follow-up favours PCV rather than SV +P.

Adult↗

The effect of parietal cell vagotomy and selective vagotomy with pyloroplasty on gastric acid secretion. A prospective randomized study.

The insulin- and pentagastrin-stimulated gastric acid secretion was studied before and 1 week, 1 month, 6 months and 1 year after parietal cell vagotomy (PCV) and selective vagotomy with pyloroplasty (SV + P) in 50 patients who took part in a consecutive randomized trial. The randomization and the operations were performed in such a way that the extent of the denervation of the proximal stomach was identical in the two groups. Basal acid output and the insulin-stimulated acid secretion were significantly increased from 1 month to 1 year after PCV, while there was no such increase after SV + P. There was no change of the pentagastrin-stimulated acid secretion (PAOP) from 6 to 12 months in either groups. One year postoperatively PAOP was significantly greater after PCV than after SV + P. The results are compatible with vagal reinnervation after PCV and support the assumption of a sprouting from the innervated gastric antrum.

Adult↗

Ileostomy.

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Animals↗

Gastric emptying after different surgical procedures for duodenal ulcer.

Gastric emptying has been studied in patients operated upon for duodenal ulcer by either 1) parietal cell vagotomy without or 2) with pyloroplasty, 3) truncal vagotomy combined with pyloroplasty or 4) antral resection, 5) gastric resection a.m. Billroth I or 6) Billroth II. Isotonic saline and 10% glucose solution have been used as test meals. Volumes of meal remaining 10 and 30 minutes after the instillations of the saline and the glucose meal respectively have been estimated. After parietal cell vagotomy without pylorplasty (PCV) the gastric emptying rate of 10% glucose solution was significantly faster than in unoperated duodenal ulcer patients. After all the other surgical procedures the gastric emptying rate of saline as well as of glucose solution was in turns significantly faster than after PCV. These results indicate the importance of the antrum-pyloric region for the control of gastric emptying rate of isotonic saline and hyperosmolar glucose solution.

Duodenal Ulcer↗

Anorectal function after major resections of the sacrum with bilateral or unilateral sacrifice of sacral nerves.

The anorectal function in 3 patients with bilateral and 4 patients with unilateral well-defined loss of sacral nerves after radical tumour excision was studied by clinical examination and by simultaneous registration of the following variables: volume and pressure in the rectum, pressure in the internal anal sphincter area and myoelectrical activity in the external anal sphincter. The patients with bilateral loss of sacral nerves had serious impairment of function. Constipation was their only safeguard against incontinence. The preservation of the first and second sacral nerves bilaterally was not sufficient for discrimination between different qualities of rectal contents passing the anal canal. The sensation of rectal distension was also impaired. The reflex pattern of the internal anal sphincter was, however, intact. The external anal sphincter displayed a weak spontaneous myoelectrical activity in the patients who had at least one second sacral nerve intact, and a weak increase of the activity could be induced voluntarily. The normal transient increase of myoelectrical discharge from the external anal sphincter in response to rectal distension could not, however, be elicited. In patients with total unilateral loss of the sacral nerves no significant impairment of anorectal function was noted. Total one-sided denervation implied deficient sensibility of the anal canal unilaterally, but no disturbance of sphincter function as judged from the reflex response of the internal and external anal sphincters to rectal distension.

Adult↗

The vagal control of the ileo-cecal sphincter in the cat.

In acute experiments on chloralosed cats the effect of efferent cervical vagal stimulation on a flow through the ileo-cecal sphincter (ICS) was studied. The motor activity of the jejunum, ileum and large intestine adjacent to the sphincter was recorded simultaneously. Vagal stimulation caused a decrease in the transphincteric flow and increased motor activity in the ileum. Increased motor activity in the proximal colon was recorded only occasionally. When the vagal nerves were stimulated during continuous splachine stimulation the transsphincteric flow was decreased although the tone and motility of the ileum was suppressed. Furthermore, guanethidine (1-3 mg/kg b.w.) blocked or suppressed the effect of vagal stimulation on the transsphincteric flow while the excitatory response of the proximal colon was greatly enhanced. This indicates that the reduction of the transsphinctteric flow following vagal stimulation was at least partly due to a direct effect of the vagal nerves on the sphincteric muscle and not to a squeezing effect of that part of the colonic wall that surrounds the sphincter. Atropine (0.1 and 1 mg/kg b.w.) blocked all responses to vagal stimulation. Thus, both guanethidine and atropine blocked the vagally induced contraction of the ICS. Relaxation to the ICS was never obtained by vagal stimulation even when the tone of the sphincter had been increased by infusion of noradrenaline.

Animals↗

Vagal influence on serotonin concentration in enterochromaffin cells in the cat.

The intracellular concentrations of 5-HT in enterochromaffin cells of the jejunum, midgut and ileum of the cat have been estimated by a cytofluorimetric method before and after various periods of peripheral vagal nerve stimulation. The fluorescence intensities in randomized cell samples were measured photometrically after a standard illumination time before and after nerve stimulation. A significant decrease in 5-HT concentration in the enterochromaffin cells all through the small intestine could be demonstrated, which is in support of the hypothesis of a neurogenic release of 5-HT from enterochromaffin cells, possibly caused by vagal adrenergic fibres.

Animals↗

A possible vagal adrenergic release of serotonin from enterochromaffin cells in the cat.

The intracellular concentrations of serotonin (5-HT) in enterochromaffin cells (EC) in the cat small intestine have been studied by a cytofluorimetric method before and after long-lasting efferent vagal nerve stimulation in the neck. Such stimulation induces a decrease of 5-HT in EC of the gut as observed previously. Pretreatment with atropine could not block this decrease, suggesting a noncholinergic mechanism. Pretreatment with a beta-blocking agent, propranolol, or bilateral removal of the superior cervical ganglia could, however, block this 5-HT decrease. Pretreatment with an alpha-blocking agent, phenoxybenzamine, caused an increase in the 5-HT content of EC both with and without nerve stimulation; the reason for this is obscure. The results indicate, that vagal nerve stimulation induces a neurogenic 5-HT release from EC in the gut, and that adrenergic fibres, originating in the superior cervical ganglia, mediate this release probably via a beta-receptor mechanism. Whether or not an alpha-receptor mechanism is also involved cannot be judged at present.

Animals↗

Sympathetic nervous control of cat ileocecal sphincter.

A perfusion method was designed in order to investigate that effects of stimulation of the splanchnic and lumbar colonic nerves on the ileocecal sphincter (ICS) of the cat. Splanchnic and lumbar colonic nerve stimulation at physiological frequencies, i.e., below 10-12 impulses/s, elicited a contraction of the sphincter concomitant with an inhibition of the motility of the adjacent parts of the small and large intestines. It is concluded that the splanchinc and lumbar colonic nerves contract the ICS by a direct effect on the sphincter and not via a contraction of the intestine surrounding the sphincter. Guanethidine and phenoxybenzamine but not propranolol blocked the contraction of the ICS. It is suggested that the splanchnic and lumbar colonic nerves control the sphincter via an alpha-adrenergic mechanism. Inhibitory fibers within the splanchnic or lumbar colonic nerves to the ICS were not found. The excitatory in the ICS elicited by adrenaline, nor-adrenaline, or phyenylephrine infusion was completely blocked by phenoxybenzamine. Propranolol did not block the effect on ICS of these drugs. On the contrary, an augmented response could be shown, indicating unmasking of an excitatory alpha-receptor response by blockade of inhibitory beta-receptors. Further support for these inhibitory beta-receptors was provided by the finding that isoprenaline had a relaxing effect on the sphincteric muscle, an effect that was blocked by propranolol. In order to block the inhibitory effect on the small and large intestine elicited by splanchnic and lumbar colonic nerve stimulation, both phenoxybenzamine and propranolol had to be administered.

Animals↗

A comparison of small intestinal transit time between the rat and the guinea-pig.

The small intestinal transit was compared in rats and guinea-pigs. A radioactive test substance (polyvinylpyrrolidone labelled with I125) was given directly into the duodenum and the distribution of the isotope in the small bowel was recorded. The small intestine was removed 10 and 20 min after the injection and deep frozen. The frozen intestine was later cut in 20 segments of equal length and the amount of isotope within each of the intestinal segments was recorded by means of a gamma counter. For each animal a propulsion diagram was constructed showing the relative percentage of isotope distributed in the 20 bowel segments. After 20 min the isotope peak was found in the ileo-caecal region in the guinea-pigs whereas 50% of the isotope had passed only half of the small intestine in the rats during the same period of time. The length of the intestine in rats passed by 75%, 50% and 25% of the isotope after 20 min was the same as that found in guinea-pigs 10 min after the injection of the isotope into the duodenum. Thus, there seems to be a marked difference in propulsive activity between rats and guinea-pigs.

Animals↗

Catecholamine-containing nerve fibres in the human abdominal vagus.

The vagal nerve of man has been investigated for the presence of adrenergic nerve fibres using the histochemical fluorescence method of Hillarp and Falck. Following 30-60 min of nerve ligation during surgical operations, the right anterior main trunk (subdiafragmatic level) from one patient, and the anterior nerve of Latarget of 5 patients were found to contain unmyelinated nerve fibres with accumulations of green fluorescent material representing a catecholamine. The observations indicate the presence of adrenergic nerve fibres running caudally in the human vagal nerve, in accordance with similar findings in other mammals, e.g. cats and dogs.

Abdomen↗

Control factors in the release of gastrin by direct electrical stimulation of the vagus.

The release of gastrin by direct electrical stimulation of the vagus was studied together with the relative effects on the response of antral and duodenal acidification. As expected, gastrin levels increased to three times the normal simulated response following antral neutralization. In contrast, duodenal acidification failed to influence the vagal release of gastrin when the antrum was neutralized although it had a minor effect when the antrum was acidified. Thus the antral pH dominates over duodenal pH as a factor in controlling gastrin release. Surprisingly, atropine in doses which blocked acid release and produced marked cardiac effects failed to inhibit the release of gastrin from the antrum on vagal stimulation. This suggests that, using this model, vagal release of gastrin, if cholinergic, is highly resistant to atropine.

Animals↗

Reflexogenic contraction of the ileo-cecal sphincter in the cat following small or large intestinal distension.

The effect of distension of a small or large intestinal loop on the ileo-cecal sphincter (ICS) in the cat was studied with a flow-recording technique. Distension of a small or large intestinal loop, isolated from the adjacent intestine, but with its mesenteric vascular and nervous supply intact, elicited a contraction of the ICS concomitant with an inhibition of the adjacent large and small intestinal motility. Vagal and pelvic nerve section did not affect the response to distension of the ICS nor exclusion of the adrenal glands from the circulation. The sphincter reflex could be entirely or almost entirely eliminated by cutting both the splanchnic and lumbar colonic nerves, but not one or the other. Spinal anesthesia bocked the reflex response indicating a spinal reflex arc. The reflex persisted after atropine and propranolol, while both guanethidine and phenoxybenzamine completely abolished the reflex contraction of the sphincter. The present results indicate that the excitatory intestino-ileo-cecal sphincteric reflex is a spinal reflex with the main afferent and/or efferent fibres located within the major splanchnic and lumbar colonic nerves. The excitatory motor response in the sphincter is adrenergic and mediated via alpha-receptors.

Animals↗