首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
BACKGROUND: How Helicobacter pylori infection affects gastric acid secretion is still unclear. METHODS: Gastric juice pH, ammonia concentration in gastric juice, serum gastrin level, and grade of gastritis in accordance with the Sydney System were determined for patients with gastric ulcer (GU) and duodenal ulcer (DU) before and after treatment with lansoprazole and amoxicillin, and results were compared with those of H. pylori-negative controls. RESULTS: Scores for H. pylori density, atrophy, metaplasia, and activity of gastritis in the corpus were higher in patients with GU, especially those with proximally located GU, than in those with DU. Gastric juice pH was significantly higher in GU patients than in DU patients and controls. After H. pylori eradication, gastric juice pH and serum gastrin levels in both GU and DU patients were significantly decreased to control levels. In patients without eradication, no significant changes in these factors were observed. CONCLUSIONS: These findings suggest that H. pylori infection and gastritis in the corpus suppress acid secretion and increase gastric juice pH, resulting in hypergastrinemia, and that eradication of H. pylori normalizes acid secretion and serum gastrin levels.  相似文献   

2.
Current concepts on the pathophysiology of gastric hypersecretion in duodenal ulcer disease have been presented and the role of vagal nerves and gastrointestinal hormones particularly gastrin has been discussed. Duodenal ulcer patients form a heterogenous group with regard to the gastric acid and pepsin secretion and gastrin release. They may differ from healthy subjects by several wall defined defects including an increased mass of parietal and peptic cells, increased capacity to secrete acid and pepsin, increased vagal drive to the parietal cells, hyperreactivity of antrum, decreased effectiveness of antral and duodenal autoregulatory mechanisms, defective release of secretin, increased gastric emptying and defective removal of gastric acid load from the duodenum. Very little is known what proportion of duodenal ulcer patients suffer from various pathologic disturbences and what are the mechanisms underlying these changes.  相似文献   

3.
BACKGROUND: The effect of infection by Helicobacter pylori on gastric physiology in duodenal ulcer subjects is controversial. There is evidence that the infection is associated with abnormalities in gastrin homeostasis. Consistent changes in pentagastrin-stimulated acid secretory status have proved difficult to establish. This may be because patients have been studied too soon after Helicobacter pylori eradication. AIMS: To study the immediate and longer term effect of Helicobacter pylori eradication on basal and pentagastrin-stimulated acid secretion in duodenal ulcer subjects. PATIENTS AND METHODS: Patients with active duodenal ulcer disease were studied. Ulcers were healed with sucralfate 2 g bd or ranitidine 300 mg nocte. Helicobacter pylori eradication was attempted with bismuth-based "Triple Therapy", and the nine patients in whom the organism was successfully eradicated were followed and studied over the 12-month period. Acid secretion was studied at entry (prior to the initiation of therapy), following healing, following eradication and 12 months later. Basal, low dose (0.1 microgram/kg) and high dose (6 micrograms/kg) pentagastrin-stimulated acid secretion was determined. RESULTS: Whilst there was a tendency for basal and low dose-stimulated acid secretion to fall following eradication, in this study only the reduction in high dose-stimulated acid secretion achieved significance following eradication (entry mean = 59.6, post eradication mean = 49.6, p < 0.03). This effect of eradication on high dose pentagastrin-stimulated acid secretion was also seen at the 12-month study (mean = 48.9, p < 0.02 versus entry). CONCLUSION: The findings of this study suggests that maximally stimulated acid secretion is modestly, albeit significantly, reduced following Helicobacter pylori eradication and that this effect persists.  相似文献   

4.
BACKGROUND & AIMS: Eradication of Helicobacter pylori expedites duodenal ulcer healing and prevents recurrences. Most patients with duodenal ulcers have impaired proximal duodenal mucosal bicarbonate secretion (DMBS). In patients with inactive, healed duodenal ulcers and normal subjects, the effect of H. pylori infection on DMBS and proximal duodenal secretory function and structure were examined. METHODS: DMBS was quantitated before and after eradication of H. pylori. Mucosal structure (duodenal bulb histopathology) and function (DMBS at rest and stimulated, effect of active vs. healed ulcer and of age) were determined in patients with duodenal ulcers and normal subjects. RESULTS: In patients with duodenal ulcers, H. pylori eradication normalized proximal DMBS. Histological examination of duodenal biopsy samples was comparable in patients with duodenal ulcers and normal subjects without apparent relationship between inflammation and DMBS. Significantly impaired DMBS occurred in response to all agonists tested (luminal acid, prostaglandin E2, and cephalic-vagal stimulation) in patients with duodenal ulcers, suggesting a generalized secretory defect. Neither the presence of active (vs.inactive) ulcer nor age significantly affected bicarbonate secretion. CONCLUSIONS: In patients with duodenal ulcers, eradication of H. pylori normalized proximal DMBS and may thereby reduce ulcer recurrences. Altered DMBS in patients with duodenal ulcers was unrelated to histopathologic abnormalities. Impaired bicarbonate secretion in patients with duodenal ulcers could be caused by a cellular and/or physiological regulatory transport defect possibly related to H. pylori.  相似文献   

5.
BACKGROUND: Patients with duodenal ulcer (DU) have high basal (BAO) and peak (PAO) acid outputs. The effect of Helicobacter pylori eradication on these variables is unclear. AIM: To discover if gastric acid hypersecretion in patients with DU is caused by H pylori. PATIENTS AND METHODS: BAO, gastrin releasing peptide (GRP), and pentagastrin stimulated PAO in 10 H pylori negative controls, and in 10 H pylori positive patients with DU was measured before and six months after H pylori eradication. H pylori status was determined by histology, culture, and by the 13C-urea breath test. After collecting a 30 minute basal aspirate, GRP 40 pmol/kg/h was infused for 45 minutes, and after a 30 minute washout, pentagastrin 6 micrograms/kg was injected intramuscularly. RESULTS: Basal and stimulated acid output (PAOGRP and PAOPg) were significantly higher in H pylori positive DU than in H pylori negative controls. Six months after H pylori eradication, basal and stimulated acid outputs were all significantly lower than before H pylori eradication. CONCLUSIONS: This study has shown that BAO, PAOGRP, and PAOPg are higher in H pylori positive DU than in H pylori negative controls. All decreased significantly six months after H pylori eradication, to fall within the range of controls. These results are compatible with a hypothesis that acid hypersecretion in duodenal ulcer disease is caused by H pylori infection.  相似文献   

6.
Although until recently the reduction of gastric acid secretion was the primary aim in the treatment of peptic ulcer disease, it is now recognised that the presence of Helicobacter pylori and not only acid is required to produce duodenal ulcer. Accordingly, the part played by gastric acid has been relegated to the contributor to the effects of H pylori infection. Recent research into the pathogenesis and treatment of peptic ulcer disease suggests the locus of receptors for acid stimulants, such as acetylcholine, histamine and gastrin, to be the immune cell in the lamina propria of gastric mucosa, and not the parietal cell. Thus the effects of acid stimulants, as well as those of mediators of other gastro-intestinal functions, such as oesophageal and gastroduodenal bicarbonate secretion, may be directly transmitted to the effector cells via macrophages and plasma cells. Nitric oxide (NO) may be the agent mediating the interaction between immune and epithelial cells. If these findings are validated and confirmed in man, they may pave the way for new approaches to the treatment of acid-related disorders, resulting in therapeutic strategies that do not necessitate the eradication of H pylori.  相似文献   

7.
In this study we have determined systemic and local antibody responses against different Helicobacter pylori antigens in H. pylori-infected and noninfected subjects. In addition, we studied whether differences in antibody responses between patients with duodenal ulcers and asymptomatic H. pylori carriers might explain the different outcomes of infection. Sera and in most instances gastric aspirates were collected from 19 duodenal ulcer patients, 15 asymptomatic H. pylori carriers, and 20 noninfected subjects and assayed for specific antibodies against different H. pylori antigens, i.e., whole membrane proteins (MP), lipopolysaccharides, flagellin, urease, the neuraminyllactose binding hemagglutinin HpaA, and a 26-kDa protein, by enzyme-linked immunosorbent assay. The H. pylori-infected subjects had significantly higher antibody titers against MP, flagellin, and urease in both sera and gastric aspirates compared with the noninfected subjects. Furthermore, the antibody titers against HpaA were significantly elevated in sera but not in gastric aspirates from the infected subjects. However, no differences in antibody titers against any of the tested antigens could be detected between the duodenal ulcer patients and the asymptomatic H. pylori carriers, either in sera or in gastric aspirates.  相似文献   

8.
Helicobacter pylori infected patients have increased gastrin release which shows a marked fall after cure of the infection. Recent studies indicate that inflammatory cells and cytokines play an important role in the pathogenesis of Helicobacter-associated hypergastrinemia. Views differ regarding the impact of gastrin on acid secretion. Current evidence suggests that gastrin is responsible for at least some of the increased acid secretion seen in duodenal ulcer patients.  相似文献   

9.
The gastric juice of Helicobacter pylori-infected individuals contains substantially higher levels of phospholipase A2 (PLA2) than that of individuals who are not infected. We present a new theory for how this H. pylori-induced PLA2 activity in gastric juice may play a major role in the development of peptic ulcer disease. When activated at neutral pH (pH 6.5-7.0), PLA2 may damage the surfactant-like, phospholipid-rich layer which constitutes an important part of the mucus barrier. Pepsin and other proteases, activated at low pH (pH 1.0-3.5), may then denature and cleave PLA2-exposed proteins. Peptic ulcers therefore tend to develop in regions exposed to changing luminal pH, such as the duodenal bulb when acid production is high or normal, or in the stomach when acid secretion is low.  相似文献   

10.
We measured basal and pentagastrin-stimulated acid secretion, as well as basal and meal-stimulated plasma gastrin concentration to determine, in 67 patients affected by resistant duodenal ulcer, whether their condition could be related to gastric acid secretion and/or gastrin-related syndromes. We then compared them to 46 duodenal ulcer control patients. The outpatients were investigated consecutively. The resistant duodenal ulcer patients differed from the controls only in their higher complication rates (bleeding or perforation, P < 0.05). We identified five patients in the resistant duodenal ulcer group with Zollinger-Ellison syndrome and 12 with antral G cell hyperfunction, whereas in the control group only one patient was affected by antral G cell hyperfunction. IgG anti-Helicobacter pylori antibodies were positive for the presence of infection in 7 of the hypergastrinaemic patients. When Zollinger-Ellison syndrome or antral G cell hyperfunction were excluded, no differences could be found in gastric acid secretion, or basal and meal-stimulated plasma gastrin levels, between the resistant and control duodenal ulcer patients, except for basal acid hypersecretion (resistant duodenal ulcer 16% vs duodenal ulcer 2% P = 0.0144). In the presence of duodenal ulcer disease resistant to H2-blockers, it is mandatory to measure basal plasma gastrin concentration since it was possible to diagnose the gastrin-related syndromes, Zollinger-Ellison syndrome and antral G cell hyperfunction, in 26% of this group of patients.  相似文献   

11.
There is evidence of a two-way interaction between gastric acid secretion and H. pylori-associated gastritis. Gastric acid secretion influences the density of H. pylori colonisation, its distribution within the stomach and the severity of the mucosal inflammatory response to the infection. In addition, H. pylori gastritis alters gastric acid secretion. In subjects with a predominant antral gastritis, it increases acid secretion predisposing to duodenal ulcer, whereas in others with predominant body gastritis, acid secretion is impaired and the subjects have an increased risk of gastric cancer. The two-way interaction between acid secretion and H. pylori gastritis is observed when H. pylori-positive subjects are treated with proton pump inhibitor agents. The inhibition of acid secretion induces a body gastritis and this inflammation of the body mucosa inhibits acid secretion thus augmenting the anti-secretory effect of the drug. In this article, we discuss the interaction between gastric acid secretion and H. pylori gastritis and its importance in determining disease outcome.  相似文献   

12.
Three working diagnoses in gastric complaints are presented: aspecific gastric complaints, ulcer complaints, reflux complaints; these assist the general practitioner in formulating the initial diagnostic and pharmacological interventions and in evaluating the effects of therapy. The guidelines state that eradication treatment of Helicobacter pylori is indicated only in gastritis caused by H. pylori, grade IV bulbitis, a duodenal bulb malformation or peptic ulcers.  相似文献   

13.
AIM: To investigate the prevalence, and relation to Helicobacter pylori, of parietal cells in the duodenal bulb using a monoclonal antibody directed against H+,K(+)-ATPase (HK12.18). METHODS: Twenty six patients with duodenal ulcer disease and 16 healthy controls were studied. H pylori status was determined by gastric histology and culture and by the 13C-urea breath test. Four biopsy specimens were taken from the duodenal bulb and stained with HK12.18. The presence/absence and number of parietal cells in the duodenal bulb were assessed blindly by a histopathologist. RESULTS: The overall prevalence of parietal cells in the duodenal bulb was 31% (13/42) and was similar in patients with duodenal ulcer and in controls, and in H pylori positive and negative subjects. The median (range) number of parietal cells in the duodenal bulb was 7.5 (4-20) parietal cells/subject, and was similar in all four groups. CONCLUSIONS: The prevalence of parietal cells in the duodenal bulb (31%) is notably higher than previously reported in endoscopic studies, and is in keeping with reports from studies on necropsy/operative specimens. There was no difference in the prevalence or number of parietal cells in the duodenal bulb between patients with duodenal ulcer and controls, regardless of H pylori status. These findings suggest that parietal cells in the duodenal bulb do not contribute to the pathogenesis of duodenal ulcer.  相似文献   

14.
BACKGROUND & AIMS: There have been conflicting reports regarding acid secretion after treatment with omeprazole. This study examined acid secretion after treatment with omeprazole and its relation to Helicobacter pylori status and on-treatment gastric function. METHODS: Twelve H. pylori-negative and 9 H. pylori-positive subjects were examined before, on, and at day 15 after an 8-week course of 40 mg/day omeprazole. On each occasion, plasma gastrin, intragastric pH, and acid output were measured basally and in response to increasing doses of gastrin 17. RESULTS: In the H. pylori-negative subjects at day 15 after omeprazole treatment, basal acid output was 82% higher (P < 0.007) and maximal acid output 28% higher (P < 0.003) than before omeprazole. The degree of increase in maximal acid output was related to both on-treatment pH and on-treatment fasting gastrin levels, being 48.0% in subjects with an on-treatment pH of >4 vs. 21. 0% in those with a pH of <4 (P < 0.02) and 49.2% in subjects with an on-treatment gastrin of >25 ng. L-1 vs. 19.8% in those with a fasting gastrin of <25 ng. L-1 (P < 0.006). At day 15 after omeprazole treatment, the H. pylori-positive subjects showed a heterogeneous response with some having increased acid output and others persisting suppression. CONCLUSIONS: Rebound acid hypersecretion occurs in H. pylori-negative subjects after omeprazole treatment. Its severity is related to the degree of elevation of pH on treatment. Persisting suppression of acid secretion masks the phenomenon in H. pylori-positive subjects.  相似文献   

15.
The fact that H. pylori gastritis results in an increased secretion of basal and meal-stimulated gastrin, which is also a physiologic amplifier of insulin release directed us to investigate whether H. pylori gastritis may lead to an enhancement of nutrient-stimulated insulin secretion. For this purpose, we have investigated the insulin responses to both oral glucose and a mixed meal in 15 patients with H. pylori gastritis before and one month after the eradication therapy and also in 15 H. pylori-negative control subjects. The areas under the curve (AUC) for serum insulin following both oral glucose and a mixed meal in the patients with H. pylori gastritis before the eradication were significantly (P < 0.05) higher than those in the H. pylori-negative controls. After the eradication of H. pylori, the AUC for serum insulin following oral glucose and mixed meal decreased by 9.4% and 13.1%, respectively (P < 0.001 in both), and serum basal and meal-stimulated gastrin levels decreased significantly (P < 0.001). These results suggest that H. pylori gastritis enhances glucose and meal-stimulated insulin release probably by increasing gastrin secretion.  相似文献   

16.
Helicobacter pylori infection increases the serum concentration of gastrin, and this may be one of the mechanisms by which it predisposes to duodenal ulceration. Different forms of circulating gastrin were studied both basally and postprandially in 13 duodenal ulcer patients before and one month after eradication of H pylori. Three antisera that are specific for particular regions of the gastrin molecules were used. Gel chromatography indicated that > 90% of the circulating gastrin consisted of gastrin (G) 17 and G34 both before and after eradicating the infection. The basal median total immunoreactive gastrin concentration fell from 26 pmol/l (range 11-43) to 19 pmol/l (8-39) (p < 0.05), entirely because of a fall in G17 from 6 pmol/l (< 2.4-25) to < 2.4 pmol/l (< 2.4-23) (p < 0.001). The median (range) basal G34 values were similar before (15 pmol (2-36)) and after (10 pmol (2-30)) eradication. The median total immunoreactive gastrin concentration determined 20 minutes postprandially fell from 59 pmol/l (38-114) to 33 pmol/l (19-88) (p < 0.005), and again this was entirely the result of a fall in G17 from 43 pmol/l (9-95) to 17 pmol/l (< 2.4-52) (p < 0.001). The median postprandial G34 values were similar before (13 pmol/l, range 6-42) and after (15 pmol/l, range 6-30) eradication. Eating stimulated a noticeable rise in G17 but little change in G34, both in the presence and absence of H pylori. The finding that H pylori infection selectively increases G17 explains why the infection causes mainly postprandial hypergastrinaemia. G17 is increased selectively because H pylori predominantly affects the antral mucosa which is the main source of G17 whereas G34 is mainly duodenal in origin. This study also indicates that the increased concentration of gastrin in H pylori infection is the result of an increase in one of the main biologically active forms of the hormone.  相似文献   

17.
The eradication of Helicobacter pylori (Hp) is known to reduce the recurrence rate of duodenal ulcer (DU) to similar extent as gastrectomy but it is not clear what is the prevalence of Hp in DU patients after surgical interventions such as gastrectomy or vagotomy. The purpose of this study was to evaluate the influence of gastrectomy or truncal vagotomy with pyloroplasty on the prevalence of Hp in 51 DU patients just before and 6-8 months after these procedures. Using C14-urea breath test (UTB), rapid CLO-test and histology of the biopsy samples of gastric mucosa obtained during gastroscopy, the Hp was detected in all DU subjects submitted to operation. Following distal gastric resection (antrectomy) with Billroth II anastomosis (N = 32) due to an ulcer resistance to conservative therapy, peptic ulceration was not observed during 6-8 months in any of the examined subjects and the Hp was only rarely observed (only in 3 out of 32 operated patients). Histologically, in antral biopsies taken prior to surgery, all DU patients presented chronic active gastritis. After the surgery, the absence of Hp was confirmed also by histology. Histological evaluation of gastrectomy stump biopsies revealed typical chronic gastritis with concomitant foveolar hyperplasia and focal gland dilation. Following selective vagotomy and pyloroplasty (N = 19), the scarring of duodenal bulb (without active ulcer) was seen in 4 out of 19 operated patients but the Hp was detected in all (100%) cases. Gastric biopsies prior and after vagotomy revealed chronic active gastritis associated with Hp infection. Basal plasma gastrin was reduced after gastrectomy by about 30% and basal and maximal pentagastrin-induced acid secretion was decreased by about 60% and 70%, respectively. Vagotomy did not reduce activity of the mucosal inflammation and the incidence of Hp. Basal plasma gastrin level was increased by about 60%, while basal and pentagastrin induced acid secretion was decreased by 25% and 40%, respectively. Because of the high ulcer recurrence rate after vagotomy as opposed to low recurrence after gastrectomy, it is reasonable to conclude that (1) the disappearance of Hp and reduction in plasma gastrin and gastric acid secretion were probably the major factors responsible for the high efficacy of gastrectomy in prevention of ulcer recurrence, (2) in non-complicated DU, gastric surgery should be avoided and replaced by conservative anti-Hp therapy involving both antisecretory or bismuth agents and antimicrobial drugs which should provide similar therapeutic effects as surgery and (3) vagotomy should be eliminated as the method of treatment of DU because of the high recurrence of peptic ulceration and the failure of this procedure to affect the Hp status.  相似文献   

18.
BACKGROUND: The presence of gastric metaplasia allows helicobacter pylori to colonise the duodenum and this condition is thought to be acquired as a response to acid hypersecretion. This functional disorder, however, is present only in a subgroup of duodenal ulcer patients and, in addition, surface gastric metaplasia has been frequently found in the proximal duodenum of normal subjects and patients with non-ulcer dyspepsia, who cannot be certainly considered as acid hypersecretors. AIMS: To clarify the role of acid in inducing gastric type epithelium in the duodenum. This study aimed at assessing whether the pattern of circadian gastric acidity differs between H pylori positive duodenal ulcer patients with and without duodenal gastric metaplasia. PATIENTS: Seventy one patients with duodenal ulcer confirmed by endoscopy and who were found to be positive for H pylori infection by histology on antrum biopsy specimens were enrolled into this study. METHODS: Gastric type epithelium in the duodenum was found in 49 of 71 ulcer patients (69%). Continuous 24 hour gastric pH metry was performed in 50 healthy subjects and in the two subgroups of duodenal ulcer patients with and without gastric metaplasia in the duodenum. Gastric acidity was calculated for 24 hours (1700-1659), night (2000-0759) and day-time (0800-1959). RESULTS: Ulcer patients without gastric metaplasia showed a significantly higher gastric acidity (p < 0.001) than controls for every time interval considered, while the ulcer subgroup with gastric metaplasia was more acid than healthy subjects (p < 0.001) during the whole 24 hour period and the daytime. There was no difference between the two subgroups of duodenal ulcer patients with and without gastric metaplasia during the various time segments analysed. CONCLUSION: The findings confirm that the circadian gastric acidity of duodenal ulcer patients is higher than that of controls. As there is no difference in gastric pH between duodenal ulcer patients with and without gastric metaplasia, gastric hyperacidity is not specific to patients with duodenal gastric metaplasia. It is probable that this histological change is a non-specific response to mucosal injury resulting from various factors and not exclusively to acid.  相似文献   

19.
BACKGROUND/AIMS: The purpose of this study was to delineate the alterations in gastric physiology after pylorus-preserving duodenectomy (PPD). METHODOLOGY: The duodenum was transected 2 cm distal to the pyloric ring in five dogs. A patch graft around the papilla of Vater was preserved. Reconstruction was completed using an end-to-end duodenojejunostomy, anastomosis of the patch graft to the jejunum, and cholecystojejunostomy, in that order. Gastric acid analysis, serum gastrin and secretin concentrations, and gastric emptying were investigated before and one and three months after surgery. RESULTS: The postoperative mean basal and maximal acid outputs were not significantly increased. Fasting serum gastrin concentrations remained unchanged. The fasting serum secretin concentrations one month after surgery increased significantly as compared to the controls. There were no significant differences in meal-stimulated gastrin or secretin responses or gastric emptying after surgery. CONCLUSIONS: The acid output and gut hormone release after PPD were maintained at preoperative levels. Preservation of the duodenal bulb is postulated to be responsible for the maintenance of near-normal gastric physiology.  相似文献   

20.
BACKGROUND/AIMS: To evaluate whether the addition of 2 weeks of ranitidine to a 1-week oral triple therapy (OTT) regimen improved ulcer healing and H. pylori eradication. METHODOLOGY: Two hundred and eleven consecutive patients with an endoscopic diagnosis of active duodenal ulcer (DU) and a positive antrum biopsy for H. pylori were enrolled. Those attending the Hospital Vera Cruz (Group A, n=142) received a 14-day course of ranitidine (150 mg after breakfast and dinner) plus a 1-week OTT, consisting of bismuth subcitrate, (240 mg after the 3 meals), tetracycline (500 mg, 10 min before the three meals and at bedtime), and furazolidone (200 mg after breakfast and dinner). Patients from the Hospital das Clinicas (Group B, n=69) received the same OTT as Group A but without ranitidine. Patients underwent endoscopy again on average 40 days (range: 30-60 days) after completing therapy in order to assess ulcer healing and H. pylori status. RESULTS: Both schedules were equally efficient in eradicating H. pylori with 90% (128/142) eradication in group A, and 84% (58/69) in group B (p=0.2). In contrast, the addition of ranitidine to OTT improved ulcer healing when compared with OTT alone (96%, 137/142, vs. 70%, 48/69; p<0.001). CONCLUSIONS: Our results demonstrate that the association of acid suppression, obtained with 2 week ranitidine administration with OTT improved ulcer healing but did not enhance H. pylori eradication.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号