Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PYLORUS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2002

Functional characteristics of the pylorus in patients undergoing pylorus--preserving gastrectomy for early gastric cancer.

BACKGROUND: This study investigates the functional characteristics of the pylorus in patients undergoing pylorus-preserving gastrectomy (PPG) for early gastric cancer. METHODS: In study 1, postprandial symptoms and gastric emptying were compared between 2 groups of 12 patients with early gastric cancer more than 1 year after either PPG (PPG group) or distal gastrectomy (DG) (DG group). Gastric emptying was evaluated with the dual isotope technique for liquids and solids separately. In study 2, pyloric motility was evaluated with a sleeve/sidehole manometric assembly in 7 patients undergoing PPG, which was compared with that in the preoperative patients. RESULTS: In study 1, the overall modified Visick score of postprandial symptoms and the Sigstad dumping score were significantly lower in the PPG group compared with the DG group (P <.05). Early accelerated gastric emptying was observed in both groups for liquids, but only in the DG group for solids. In study 2, isolated pyloric pressure waves induced by intraduodenal lipid infusion and phase III-like activity induced by intravenous erythromycin infusion were preserved after PPG. CONCLUSIONS: The quantitative analysis of postoperative symptoms revealed that PPG patients were associated with better clinical conditions than DG patients. The clinical benefits of PPG are considered to be based on the function of the preserved pylorus.

Adult↗
PubMed2000

Effect of denervation of the pylorus and transection of the duodenum on acetaminophen absorption in rats; possible mechanism for early delayed gastric emptying after pylorus preserving pancreatoduodenectomy.

Early delayed gastric emptying has been reported as a frequent complication following pylorus preserving pancreatoduodenectomy (PPPD). We investigated the effect of division of the pyloric branch of the vagus nerve and/or transection of the duodenum on gastric emptying using the acetaminophen method in rats to speculate the unknown etiology of early delayed gastric emptying after PPPD. Twenty-four male Wistar rats were divided into the following four groups; Group S, sham operation as controls; Group N, disturbance of neuro-vascular supply to the pylorus; Group D, temporary interference of the duodenal continuity; and Group N+D, with both procedures in Group N and Group D. Gastric emptying was measured using the acetaminophen method at 1, 2, and 4 weeks after operations in each group. No significant difference was observed in Group S at any intervals after the operation. Gastric emptying was prolonged significantly in Group N, Group D and Group N+D compared to Group S until 2 weeks following surgery. Significant delayed gastric emptying was sustained in Group N+D at 4 weeks, although gastric emptying in Group N and Group D was improved by 4 weeks. The results in rodent models suggest that both dissection of the pyloric branch of the vagus and transection of the duodenum might be causative factors of postoperative delayed gastric emptying following PPPD.

Acetaminophen↗
PubMedDate not supplied

[A comparative evaluation of the efficacy of pylorus-destroying and pylorus-preserving operations with vagotomy in bleeding duodenal ulcers].

Results are analyzed of surgical treatment of 230 patients with duodenal ulcer complicated by bleeding, who underwent vagotomy and pylorus-nonsparing and pylorus-sparing operations. Of these, 110 patients were subjected to vagotomy involving pyloroplasty, 120 to selective proximal vagotomy with duodenoplasty. Results of postoperative 3- to 5-yr survival are analyzed. A method is suggested for treatment of postvagotomy syndromes.

Adult↗
PubMed1997

[Substantiation and choice of pylorus preserving and pylorus destructive surgery with vagotomy in ulcer of the pyloroduodenal zone with hemorrhage].

The results of examination and surgical treatment of 230 patients with duodenal ulcer, complicated by haemorrhage, were analyzed. Vagotomy with pyloroplasty was conducted in 110 patients, vagotomy with duodenoplasty--in 120. The algorithm of operations conduction was elaborated, the results of treatment of patients in terms up to 5 years were estimated.

Adult↗
PubMedDate not supplied

The importance of the pylorus as a regulator of solid and liquid emptying from the stomach.

The role of the pylorus in the control of gastric emptying of liquids and digestible solids was investigated in the present study by pylorus excision in six pigs. The pylorus was left intact in another six pigs. Antro-pyloro-duodenal motility was recorded by a sleeve sensor and side holes. Liquid emptying was significantly more rapid in pylorus excised than in pylorus intact animals, during intraduodenal infusion of isosmolar dextrose (712 mL vs 107 mL), fatty acid (402 mL vs 46 mL), amino acids (752 mL vs 112 mL), 25% dextrose (392 mL vs 51 mL) and 3 normal saline (705 mL vs 157 mL). In pylorus excised animals, in contrast to pylorus intact animals, the manometric pattern of isolated pyloric pressure waves at the distal stomach was rarely seen (P < 0.05). In a second series of experiments, pylorus excised animals emptied significantly more (P < 0.04) meat over 120 min (181 g) than pylorus intact animals (80 g), but the proportion of particle sizes emptied was unaltered. In the pig, localized pyloric contractions are important for retardation of gastric emptying when nutrient or hyperosmolar solutions enter the duodenum. By contrast, the pylorus is unimportant in determining the size of solid particles emptied from the stomach.

Animals↗
PubMed1976

[Electromyographic studies on gastric and intestinal motor function following pylorus preserving gastrectomy with jejunal interposition in dogs (author's transl)].

The gastric and intestinal motor function following pylorus preserving gastrectomy with jejunal interposition were studied electromyographically in dogs. The action potentials were recorded from the interposed jejunal segment, the preserving pylorus and the duodenum before and after insertion of warm water. Studies were made on the frequency, the propagation velocity of the spike-bursts in the portions mentioned above, and the incidence of the spike-bursts which propagated from the distal porition of the interposed jejunal segment to the preserving pylorus, and from the preserving pylorus to the proximal portion of the duodenum. The results obtained are as follows: 1) The frequency of the spike-bursts found in the interposed jejunal segment, the preserving pylorus, and the duodenum showed a remarkable increase after insertion of warm water. 2) The propagation velocity of the spike-bursts in the interposed jejunal segment, the preserving pylorus, and the duodenum were accelerated after insertion of warm water. 3) There were observed a moderate increase in the incidence of the spike-bursts which propagated from the distal portion of the interposed jejunal segment to the preserving pylorus, and from the preserving pylorus to the proximal portion of the duodenum after insertion of warm water. These findings suggested that the motor function of the interposed jejunal segment, that of the preserving pylorus, and that of the duodenum after pylorus preserving gastrectomy with jejunal interposition might be kept not yet injured enough to transport the contents from the interposed jejunal segment into the duodenum.

Action Potentials↗
PubMed1980

Mechanisms of gastric acid secretion after pylorus and oesophagus ligation in the rat.

1. The effect of vagotomy on gastric acid secretion was studied in chronic gastric fistula rats at various times after denervation. In these rats basal and pentagastrin-induced acid output was permanently reduced. Thus, the magnitude of the acid response to pentagastrin in the conscious fistula rat is dependent upon an intact vagus. 2. The acid response to pylorus ligation in vagally intact rats was unaffected by drainage of the stomach and therefore not caused by distension. Bilateral vagotomy, performed simultaneously with the ligation, completely abolished acid secretion, while unilateral vagotomy reduced the acid output by half. Hence, in innervated rats, an intact vagal impulse flow appears to be essential for the acid response to pylorus ligation. When the pylorus ligation was performed 2-8 weeks after truncal vagotomy, the acid output showed a progressive return towards pre-denervation values. In the denervated rats the acid response to pylorus ligation was blocked by drainage of the stomach and therefore probably caused by distension, a mechanism which is independent of the vagal impulse flow. 3. The response to pylorus ligation in innervated rats was blocked by atropine and chlorisondamine but not by metiamide. In the denervated rats, the response to pylorus ligation was blocked by all three drugs. 4. Following ligation of both the pylorus and the oesophagus the acid response was poor. With drainage of the oesophagus the acid response was much enhanced, suggesting that oesophageal distension inhibits acid secretion. In the vagotomized rat the poor acid response to oesophageal + pyloric ligation could not be overcome by drainage of the oesophagus. In the innervated rat gastric distension could overcome the inhibition induced by oesophageal ligation. Also in chronically, but not in acutely vagotomized rats, gastric distension brought about a good acid response. Conceivably, gastric reflex mechanisms can activate acid secretion through vagal and/or intramural pathways. Both in innervated and denervated rats the response to gastric distension was inhibited by atropine, chlorisondamine and metiamide. 5. The results suggest that in the innervated rat vago-vagal reflexes are important for the gastric hypersecretion following ligation of the pylorus, and for the acid response to gastric distension following ligation of the pylorus and oesophagus. In the chronically vagotomized rat local intramural reflexes elicited by gastric distension are responsible for the acid response.

Animals↗
PubMed1982

Gastric acid response to pylorus ligation in rats: is gastrin or histamine involved?

1. Pylorus ligation stimulated the acid output in vagally intact rats. The serum gastrin concentration and the gastric mucosal histamine content were not affected. The gastric histidine decarboxylase activity was initially slightly elevated and then greatly reduced (12-20 hr after ligation).2. Pylorus ligation stimulated the acid output in chronically, but not in acutely, vagotomized rats. Chronic vagotomy raises the serum gastrin concentration, the gastric histamine content and histidine decarboxylase activity. The serum gastrin concentration was further raised by pylorus ligation. The histamine content was initially lowered but returned to preligation values after 20 hr. The histidine decarboxylase activity first decreased, but increased to very high levels 5-6 hr after ligation. Twelve hours after ligation it was lower than before ligation.3. Following pylorus ligation pentagastrin and histamine stimulated the acid output in vagally intact and in acutely vagotomized but not in chronically vagotomized rats. By contrast, pentagastrin raised the histidine decarboxylase activity in vagally intact and in chronically vagotomized, but not in acutely vagotomized rats.4. The two major populations of endocrine cells of the oxyntic gland area (ECL cells and A-like cells) are argyrophil, store histamine and are capable of taking up exogenous DOPA and of decarboxylating it to dopamine which is retained in the cytoplasm for several hours. As evidenced by light and fluorescence microscopy pylorus ligation did not affect their argyrophilia or their ability to produce and store dopamine.5. Pylorus ligation caused ultrastructural changes in the gastrin cells of the pyloric gland area and in the histamine-storing ECL and A-like cells of the oxyntic gland area. The two endocrine cell types in the oxyntic gland area were enlarged by pylorus ligation, more so after 16 hr than after 4 hr. The size of the gastrin cells seemed unaffected. In all three cell types pylorus ligation reduced the number of cytoplasmic granules. There was no increase in the Golgi area or in the endoplasmic reticulum in any of the endocrine cell types of the oxyntic gland area. It appears unlikely that the ultrastructural changes of the ECL and A-like cells reflect an increased rate of histamine mobilization.6. The acid response to pylorus ligation probably reflects neuronal reflex mechanisms exclusively. There is no evidence that gastrin or histamine released from gastric endocrine cells mediate the response.

Animals↗
PubMed1999

An explanation of gastric hypersecretion in the pylorus-ligated rat.

The hypersecretion of gastric acid in the pylorus-ligated rat has been shown to be of vagal origin. The present series of experiments were performed to identify the stimulus. The pyloric sphincter was ligated in a series of Sprague Dawley rats. Along with pylorus ligation, various other surgical manipulations were performed. Intestinal obstruction by ligation approximately 20 cm aboral to the cecum reduced unstimulated gastric secretion in the pylorus-ligated rat. However, perfusion of the lower small intestine with bicarbonate (143 mEq/L) stimulated secretion. Perfusion with either saline or deoxycholic acid (20 mEq/L) did not alter secretion. This supports a role for bicarbonate in the hypersecretion of gastric acid in the pylorus-ligated rat. The reflex appears to involve the myenteric plexus, since section of the pylorus seemed to attenuate gastric secretion. Plasma from animals with pylorus ligation, either alone or with intestinal ligation, equally inhibited gastric secretion. This suggests that while some factor inhibiting gastric secretion may be present, it appears to be unrelated to pylorus ligation.

Animals↗
PubMed1996

Rat stomach enterochromaffin-like cells are not stimulated by pylorus ligation. A biochemical and ultrastructural study.

BACKGROUND: The enterochromaffin-like (ECL) cells in the rat oxyntic mucosa produce histamine and contain cytoplasmic granules, microvesicles, and secretory vesicles. The cells respond to gastrin by the release of histamine (associated with loss of secretory vesicles), which is thought to mediate the gastrin-induced stimulation of the parietal cells. Gastric acid secretion is stimulated also by vagal excitation, which can be induced, for instance, by pylorus ligation. The present study addresses the question whether the ECL cells are involved in the acid response to pylorus ligation. METHODS: Rats were subjected to pylorus ligation and killed 4 or 16 h later. Other rats were subjected to sham operation (laparotomy). Some of the rats received human Leu15-gastrin-17 (5 nmol/kg/h) by intravenous infusion for 30 or 60 min before being killed. The serum gastrin concentration, the oxyntic mucosal histidine decarboxylase (HDC) activity, HDC mRNA concentration, histamine concentration, and gastric acid output were measured. Specimens from the oxyntic mucosa were processed for transmission electron microscopy. Electron micrographs of ECL cells were analyzed planimetrically. RESULTS: The gastric acid output was high, but the serum gastrin concentration was not affected by the pylorus ligation. The HDC activity and the level of HDC mRNA in the oxyntic mucosa were reduced, but the histamine concentration was unchanged. The secretory vesicles and granules of the ECL cells were unaffected, whereas the number and volume density of the microvesicles were reduced. Gastrin administration to sham-operated and pylorus-ligated rats lowered the oxyntic mucosal histamine concentration and increased the HDC activity in both groups. CONCLUSIONS: ECL cells in the rat stomach do not mediate the gastric acid response to pylorus ligation, and ECL cells in the pylorus-ligated stomach retain their ability to respond to gastrin with activation.

Animals↗
PubMed1966

The mechanism of the inhibition of gastric secretion produced by esophageal ligation in the pylorus-ligated rat.

Esophageal ligation in the pylorus-ligated rat significantly inhibited volume, titratable acidity, and titratable acid output and reduced the incidence of ulcers, perforations, and death of 18-hr pylorus-ligated rats. Draining the saliva outside the body of the rat by esophageal cannulation produced a significant increase in volume and gastric acidity over the esophagus-ligated preparation. A method for collection of saliva in the unanesthetized unstimulated rat was developed, and basal salivary flow was found to be 0.84 ml/4 hr. Administration of 1.0 ml of freshly collected saliva to esophagus + pylorus-ligated rats increased titratable acidity, but not volume of secretion, to the level found in the pylorus-ligated rat. A similar effect was obtained with administration of 1.0 ml of a phosphate buffer. Removal of the salivary glands had no significant effect on gastric acidity in the pylorus-ligated rat and the reduction in volume could be accounted for by the lack of saliva. Gastric secretion in the esophagus + pylorus-ligated rat was stimulated by histamine, carbachol, insulin, and 2-deoxyglucose. When the vagus nerves were cut, stimulation was still obtained with carbachol but not with insulin or 2-deoxyglucose. The data indicated that rat saliva did not contain a specific gastric stimulant material, and esophageal ligation depressed gastric secretion in the pylorus-ligated rat by inhibition of the central vagal activity.

Animals↗
PubMedDate not supplied

Comparison of quality of life after pylorus-preserving pancreatoduodenectomy and Whipple resection.

BACKGROUND/AIMS: There have been many supportive data that the postoperative changes in nutritional status are more favorable after pylorus-preserving pancreatoduodenectomy than after Whipple resection; however, few reports are available on the postoperative changes in subjective quality of life after pancreatoduodenectomy. The aim of this study was to compare the postoperative change in quality of life after pylorus-preserving pancreatoduodenectomy and Whipple resection. METHODOLOGY: A total of 36 patients (31 with pylorus-preserving pancreatoduodenectomy and five with Whipple resection) were studied regarding quality of life before and at short term (within two months) and at long term (six months to one year) after surgery, using a questionnaire. The questionnaire consisted of 13 physical and 10 psychosocial items. The medical records were also reviewed to evaluate their objective nutritional status. Postoperative changes in quality of life and nutritional status were compared between the pylorus-preserving pancreatoduodenectomy and Whipple groups. RESULTS: Overall and physical quality of life scores dropped at short term and then recovered at long term in the pylorus-preserving pancreatoduodenectomy group, but showed a persistently low value even at long term in the Whipple group. The change in physical quality of life showed almost parallel changes with the nutritional status in both groups. However, the scores of psychosocial quality of life, which reflected the patient's mental status, remained low even at long term in both pylorus-preserving pancreatoduodenectomy and Whipple groups. CONCLUSIONS: Quality of life is more favorable after pylorus-preserving pancreatoduodenectomy than after Whipple resection, but long-standing mental health care is necessary in patients with pyloruspreserving pancreatoduodenectomy and Whipple resection.

Activities of Daily Living↗