Topical application of benzalkonium chloride to the stomach serosa increases gastric emptying time, acid secretion, serum gastrin and size of the mucosa.

AIM: In the present study we evaluated the effects of gastric myenteric denervation using benzalkonium chloride (BAC) on the time for gastric emptying, as well as gastric secretion, and mucosal epithelial cell size and population in rats. METHODS AND RESULTS: Wistar rats were treated with topical serosal application of BAC to the stomach. Control animals received saline. Ninety days after surgery, gastric emptying time, gastric acid secretion and serum gastrin levels were studied. Next, the animals were sacrificed and the stomachs were removed, fixed in formalin and histologically processed for histomorphometry of the height, area and volume of the glandular portion, and volume and population of mucous, chief, parietal, G- and labelled cells. BAC animals showed a significant delay in gastric emptying and an increase in gastric acid secretion and serum gastrin levels. These animals also presented a significant reduction of myenteric neuron number, hypertrophy of parietal and chief cells, hyperplasia of G cells and an increase in the gastric mucosa area. CONCLUSION: The absence of the myenteric plexus seems to protect the stomach from the hyperplastic effects of hypergastrinemia. Gastric food stasis may act as a factor triggering morphological and functional alterations of the gastric epithelium. Although gastric food stasis is a common finding in medical practice, its physiopathological consequences are poorly understood and have not been frequently discussed in the literature.

Lower density of antral somatostatin-immunoreactive cells in the digestive form of chronic Chagas' disease.

Patients with the digestive form of chronic Chagas' disease exhibit abnormally increased gastrin release, possibly caused by antral gastrin cell (G cell) hyperfunction. In order to identify the mechanisms underlying this abnormality, we used an immunohistochemical method to assess the population of antral somatostatin-producing cells (D cells) in chagasic patients, since somatostatin is known to be the main inhibitory factor of gastrin secretion. Samples (N = 11) of endoscopic antral biopsies taken from 16 Chagas' disease patients and 13 control subjects were studied. Antral D and G cell populations were determined by an immunohistochemical technique using highly specific antibodies against somatostatin and gastrin. There was no significant difference between Chagas' disease and control groups regarding G cell population (number of cells/mm reported as median (range): 70.0 (23.7-247.0) vs 98.1 (52.7-169.4), P > 0.10). In contrast, the number of antral D cells in Chagas' disease patients was significantly lower than in controls (16.4 (6.9-54.4) vs 59.3 (29.6-113.8), P < 0.05). Chronic superficial gastritis and infection with Helicobacter pylori were more frequent in chagasic patients than in controls, but there was no demonstrable association between these factors and the reduction of the number of antral D cells. These data suggest that reduction in the number of antral somatostatin-producing cells, which should lead to reduced inhibition of gastrin cell activity, may play a role in the increased gastrin secretion observed in Chagas' disease patients.

Lower density of antral somatostatin-immunoreactive cells in the digestive form of chronic Chagas' disease

Patients with the digestive form of chronic Chagas' disease exhibit abnormally increased gastrin release, possibly caused by antral gastrin cell (G cell) hyperfunction. In order to identify the mechanisms underlying this abnormality, we used an immunohistochemical method to assess the population of antral somatostatin-producing cells (D cells) in chagasic patients, since somatostatin is known to be the main inhibitory factor of gastrin secretion. Samples (N = 11) of endoscopic antral biopsies taken from 16 Chagas' disease patients and 13 control subjects were studied. Antral D and G cell populations were determined by an immunohistochemical technique using highly specific antibodies against somatostatin and gastrin. There was no significant difference between Chagas' disease and control groups regarding G cell population (number of cells/mm reported as median (range): 70.0 (23.7-247.0) vs 98.1 (52.7-169.4), P>0.10). In contrast, the number of antral D cells in Chagas' disease patients was significantly lower than in controls (l6.4 (6.9-54.4) vs 59.3 (29.6-113.8), P<0.05). Chronic superficial gastritis and infection with Helicobacter pylori were more frequent in chagasic patients than in controls, but there was no demonstrable association between these factors and the reduction of the number of antral D cells. These data suggest that reduction in the number of antral somatostatin-producing cells, which should lead to reduced inhibition of gastrin cell activity, may play a role in the increased gastrin secretion observed in Chagas' disease patients.

Antral gastrin cell population in patients with chagasic megaesophagus and megacolon.

1. Patients with chronic Chagas' disease have abnormally low gastric acid secretion and increased gastrin release both during fasting and after different stimuli. Regardless of the relationship between intragastric acidity and gastrin secretion, it is uncertain whether hypergastrinemia in Chagas' disease is caused by an increased population of antral gastrin (G) cells (hyperplasia) or by enhanced cell activity (hyperfunction). 2. We therefore estimated G cell number in antral biopsies from 16 chagasic patients and 13 control subjects using a peroxidase-anti-peroxidase immunohistochemical technique. All subjects underwent a gastric secretion test to determine peak acid output following intravenous pentagastrin instillation. 3. Antral G cell number in Chagas' disease patients was not significantly different from that observed in the control group (number of cells/mm2, median and (range): 128 (44-284) vs 138 (65-285)). 4. In chagasic patients, peak acid output was significantly lower than in controls (mmol/h, median and (range): 9.819 (3.024-21.564) vs 17.490 (9.423-25.848)). 5. These results suggest that the increase in gastrin release associated with reduced gastric acid secretion in Chagas' disease is mediated by antral G cell hyperfunction rather than by hyperplasia.

Antral gastrin cell population in patients with chagasic megaesophagus and megacolon

1. Patients with chronic Chagas' disease have abnormally low gastric acid secretion and increased gastrin release both during fasting and after different stimuli. Regardless of the relationship between intragastric acidity and gastrin secretion, it is uncertain whether hypergastrinemia in Chagas' disease is caused by an increased population of antral gastrin (G) cells (hyperplasia) or by enhanced cell activity (hyperfunction). 2. We therefore estimated G cell number in antral biopsies from 16 chagasic patients and 13 control subjects using a peroxidase-anti-peroxidase immunohistochemical technique. All subjects underwent a gastric secretion test to determine peak acid output following intravenous pentagastrin instillation. 3. Antral G cell number in Chagas' disease patients was not significantly different from that observed in the control group (number of cells/mm2, median and (range): 128 (44-284) vs 138 (65-285)). 4. In chagasic patients, peak acid output was significantly lower than in controls (mmol/h, median and (range): 9.819 (3.024-21.564) vs 17.490 (9.423-25.848)). 5. These results suggest that the increase in gastrin release associated with reduced gastric acid secretion in Chagas' disease is mediated by antral G cell hyperfunction rather than by hyperplasia

Abnormal progression of a liquid meal through the stomach and small intestine in patients with Chagas' disease.

This study describes the abnormal pattern of gastrointestinal progression of a liquid meal in patients with the digestive form of chronic Chagas' disease. This condition is known as a natural model of intramural denervation of the gut. Sixteen patients with clinical and radiographic evidence of esophageal and/or colonic involvement and 18 healthy volunteers were studied. Orocecal transit time after the ingestion of a 10% lactulose solution (180 ml) tagged with 99mtechnetium was measured by a conventional H2 breath technique. Gastric emptying and the arrival of the front of the meal to regions of interest corresponding to proximal and distal areas of the small intestine were assessed by abdominal scintigraphy. Orocecal transit time was significantly greater (P < 0.05) in Chagas' disease patients (N = 13) than in control subjects (N = 18) (mean +/- SD: 100.7 +/- 48.7 min vs 62.9 +/- 18.2 min). Half-time for gastric emptying of liquids in chagasic patients (N = 9) was significantly lower (P < 0.01) than in controls (N = 7) (9.7 +/- 2.7 min vs 26.4 +/- 3.4 min). The time of arrival of the liquid meal to the proximal small intestine was also significantly shorter (P < 0.02) in patients than in controls (5.6 +/- 3.7 vs 11.4 +/- 5.5 min), but there was no difference between the two groups concerning the time the meal first arrived to the distal small intestine (15.0 +/- 11.0 min vs 23.5 +/- 11.4 min, P > 0.05). These results indicate that patients with Chagas' disease have a combination of exceedingly rapid gastric emptying and abnormally delayed transit of liquids through the more distal segments of the small bowel.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic gastritis and Helicobacter pylori in digestive form of Chagas' disease

Patients with the digestive form of Chagas' disease frequently present chronic gastritis. As the microorganism Helicobacter pylori is now accepted as the most common cause of human chronic gastritis, the present work was undertaken to verify a possible relationship between the presence of this bacterium and inflammatory changes of antral mucosa in chagasic patients. Seventeen chagasics, with megaesophagus and or megacolon were studied. Fragments from two different regions of antral mucosa were obtained by endoscopy, fixed in 4 neutral formaldehyde and embedded in paraffin. The sections were stained by haematoxylin and eosin for histology analysis, and by carbolfuchsin for H. pylori identification. H. pylori was found in 16 (94.1) chagasic patients, all of them presenting chronic gastritis. Superficial gastritis was seen in 9 (52.9) while atrophic gastritis was present in 8 (47.1) patients. H. pylori was present on gastric mucosa of 8 (100) patients with atrophic gastritis and of 8 (88.8) patients with superficial gastritis. We concluded that the microorganism H. pylori should be considered a possible factor connected with the etiopathogenesis of chronic superficial and atrophic gastritis frequently observed in patients with the digestive form of Chagas' disease.

Chronic gastritis and Helicobacter pylori in digestive form of Chagas' disease.

Patients with the digestive form of Chagas' disease frequently present chronic gastritis. As the microorganism Helicobacter pylori is now accepted as the most common cause of human chronic gastritis, the present work was undertaken to verify a possible relationship between the presence of this bacterium and inflammatory changes of antral mucosa in chagasic patients. Seventeen chagasics, with megaesophagus and or megacolon were studied. Fragments from two different regions of antral mucosa were obtained by endoscopy, fixed in 4% neutral formaldehyde and embedded in paraffin. The sections were stained by haematoxylin and eosin for histology analysis, and by carbolfuchsin for H. pylori identification. H. pylori was found in 16 (94.1%) chagasic patients, all of them presenting chronic gastritis. Superficial gastritis was seen in 9 (52.9%) while atrophic gastritis was present in 8 (47.1%) patients. H. pylori was present on gastric mucosa of 8 (100%) patients with atrophic gastritis and of 8 (88.8%) patients with superficial gastritis. We concluded that the microorganism H. pylori should be considered a possible factor connected with the etiopathogenesis of chronic superficial and atrophic gastritis frequently observed in patients with the digestive form of Chagas' disease.

[Tissue levels of 6-ketoprostaglandin Fl alpha and integrity of gastric mucosa in patients with Chagas disease]. / Níveis teciduais da prostaglandina 6-ceto-PGF 1 alpha e integridade da mucosa gástrica em pacientes com doença de Chagas.

An increased prevalence of chronic gastritis has been reported in patients with chronic Chagas' disease (American trypanosomiasis), which is regarded to be model of intrinsic denervation of the gastrointestinal tract. In order to investigate whether this condition is associated with a reduction of prostaglandin levels in gastric mucosa, we studied 14 Chagas' disease patients with megaesophagus and/or megacolon and compared them with 10 control subjects. All patients and controls underwent an upper gastrointestinal tract endoscopy where biopsies were collected from the antrum for histology and for 6-keto-PGF 1 alpha radioimmunoassay. In the Chagas' disease group, the proportion of patients with either moderate or severe gastritis (7/14) was significantly higher (p < 0.01) than in the control group (0/10). Values for antral 6-keto-PGF 1 alpha in Chagas' disease patients (median: 80.75 ng/g; range 36.5-245.6 ng/g) were slightly lower than those obtained in controls (median: 116.2 ng/g; range: 13.1-269 ng/g), but the difference was not statistically significant (p > 0.10). These results confirm previous observations suggestive of an increased prevalence of chronic gastritis in Chagas' disease, but do not support the view that chronic destruction of the intramural neurons of the gut, which is known to occur in this condition, is associated with a reduction of prostaglandin levels in gastric antral mucosa.

Effect of chlorpromazine and biliary drainage on portal blood flow and mitochondrial function during extrahepatic cholestasis.

The present study examines the effect of chlorpromazine and biliary drainage in cholestatic rats. The time course of portal blood flow was studied 24, 48, and 72 h and seven days after bile duct ligation. Portal blood flow decreased after 72 h. Chlorpromazine reduced biliary hydrostatic pressure in sham-operated control rats, but 24-h obstruction was sufficient to prevent this effect in cholestatic rats. The drug ameliorated the mitochondrial and cell membrane function of cholestatic rats before and after drainage. The data present further support for the role of ischemia in cholestasis.

Effect of chlorpromazine and biliary drainage on portal blood flow and mitochondrial function during extrahepatic cholestasis

The present study examines the effect of chlorpromazine and biliary drainage in cholestatic rats. The time course of portal blood flow was studied 24,48, and 72 h and seven days after bile duct ligation. Portal blood flow decreased after 72 h. Chlorpromazine reduced biliary hydrostatic pressure in sham-operated control rats, but 24-h obstruction was sufficient to prevent this effect in cholestatic rats. The drug ameliorated the mitochondrial and cell membrane function of cholestatic rats before and after drainage. The data present further support for the role of ischemia in cholestasis

Immediate effects of the endoscopic sphincterotomy on the motility of the sphincter of Oddi.

An endoscopic manometric technique was used to determine the CBD-duodenum junction pressure profile before and immediately after endoscopic sphincterotomy in 13 patients with common bile duct stones. Premedication (meperidine, atropine, and diazepam) was given to all patients and endoscopic retrograde cholangiopancreatography was performed before endoscopic sphincterotomy. In the patients with intact papilla the features of the sphincter of Oddi motility were similar to those previously described for patients not given premedication or submitted to cholangiography before endoscopic sphincterotomy. Endoscopic sphincterotomy which was successful for immediate stone removal in 9 of 13 patients caused an immediate reduction of sphincter of Oddi motility in all patients, but abolished it in only 2 of them. The present results show that successful common bile duct stone extraction by means of endoscopic sphincterotomy can be accomplished without total abolition of sphincter of Oddi motility.

[Incidence of diverticular disease of the large bowel in non-chagasic and chagasic individuals with and without megacolon]. / Incidência de doença diverticular do intestino grosso em indivíduos não chagásicos e em chagásicos com e sem megacólon.

To study the frequency of association between two common colonic disease in our midst, chagasic megacolon and diverticular disease, we reviewed the barium enemas of 243 patients aged more than 35 years. Diverticula were detected in 22 (21.6%) of the 102 non-chagasic individuals, in 10 (35.7%) of 20 chagasics without megacolon, and in 14 (12.4%) of the 113 chagasics with megacolon. There was a statistically significant difference between the two chagasic groups, but not between each one of them and the non-chagasic group. The incidence of diverticula in the sigmoid colon of the non-chagasic group was significantly higher than in the sigmoid colon of the other two groups studied. Among the patients with association of megacolon and diverticular disease, the diverticula were always located in the nondilated portions of the large bowel. It is suggested that totally unfavorable conditions for the genesis and/or maintenance of diverticula exist in the dilated colon of chagasic patients.