Gastroesophageal sphincter pressure and serum gastrin: reaction to food stimulation in normal subjects and in patients with gastric or duodenal ulcer

Active and inactive gastroesophageal reflux diseases related to Helicobacter pylori therapy

We systematically reviewed the literature on gastroesophageal reflux disease (GERD) related to Helicobacter pylori therapy, and classified the GERD according to various aspects. Preexisting GERD is active GERD before H. pylori therapy, and a substantial proportion of the GERD patients improve after successful H. pylori therapy. If the GERD does not persist or recur after cessation of acid-suppressive therapy combined with H. pylori therapy, it may have been cured (cured GERD). If it recurs, it may have been masked by acid-suppressive therapy and unmasked with cessation of the therapy (pharmacologically masked and unmasked GERD). Newly developed GERD after successful H. pylori therapy is a kind of unmasked GERD arising after cure of infection (de novo unmasked GERD). The possible mechanism of the improvement of cured GERD is normalized hyperacidity associated with an improved cytokine-somatostatin-gastrin system followed by normalized G-cell activity and parietal cell mass. Preexisting GERD is not a reason to avoid eradication therapy. De novo unmasked GERD develops in a substantial proportion of patients with cured infection. The possible mechanism is increased acid exposure in the esophagus due to gastric acid increase, which is caused by a loss of neutralizing effect by ammonia, normalized cytokine-acid suppression and improvement of corpus atrophy. De novo unmasked GERD is important because GERD is recurrent and may induce adenocarcinoma of the esophagus. However, it is expected that cure of infection lowers gastric cancer incidence. Eradication therapy is recommended irrespective of the possibility that de novo unmasked GERD may have a slight increase of the risk of esophageal adenocarcinoma.

Influence of food intake and postural changes on gastroesophageal sphincter pressure in patients with reflux esophagitis and in controls

The gastroesophageal sphincter pressure (GESP) was studied before, during, and after food intake in 9 reflux esophagitis patients and 11 healthy controls. A significant decrease in GESP was observed 5, 10, and 30 min after the beginning of the meal in reflux esophagitis patients, contrasting with an increase during food intake in the control group. In the supine position GESP was significantly lower than in the sitting position in esophagitis patients, contrasting with a significantly higher GESP in the supine position in the control group. These results may explain why patients with gastroesophageal reflux often develop their symptoms during food intake and in the supine position.

Gastro-oesophageal function in duodenal ulcer patients

An investigation of the gastro-oesophageal region was made in 39 patients with uncomplicated duodenal ulcer (DU). The results were compared with the results from a group of normal volunteers. The DU patients had a lower gastro-oesophageal sphincter pressure (p less than 0.05) and a reduced acid-clearing ability (p less than 0.05). Furthermore, an increased acid gastro-oesophageal reflux (p less than 0.05) and a greater number of reflux episodes lasting longer than usual (p less than 0.05) were demonstrated. There was a positive correlation between low gastro-oesophageal sphincter pressure and acid gastro-oesophageal reflux within the pH intervals 0--3 and 0--4. The peristaltic activity was measured by the number of pressure amplitudes registered in the upper and lower part of the oesophagus; an increase (p less than 0.05) in pressure amplitudes in the lower part was found in the DU patients. When time relationship was used to distinguish between propagating, simultaneous, and reversed peristaltic activity, an increase in reversed peristaltic activity (p less than 0.001) was demonstrated in DU patients. The conclusion is that DU patients have an increased acid gastro-oesophageal reflux, probably as a result of an incompetence in the gastro-oesophageal sphincter barrier, and a reduced acid-clearing ability. The peristaltic activity is increased during the reflux episodes, although this investigation does not determine whether this is due to an increased reflux volume or an insufficient peristaltic activity.

The influence of cimetidine on basal gastro-oesophageal sphincter pressure, intargastric pH, and serum gastrin concentration in normal subjects

A pressure and pH-sensitive probe has been constructed for simultaneous measurement of gastro-oesophageal sphincter pressure and intragastric pH. The coefficient of variation for measurements of the gastro-oesophageal sphincter was 0.24, and for the intragastric pH, 0.09. After peroral ingestion of 400 mg of cimetidine or placebo, simultaneous measurements of gastro-oesophageal sphincter pressure and intragastric pH were made at fixed time intervals, and at the same time blood samples were taken for determination of serum gastrin and serum cimetidine concentrations. No demonstrable difference was found in the time-course of the gastro-oesophageal sphincter pressure after ingestion of cimetidine or placebo. After ingestion of cimetidine a significant rise in intragastric pH (p less than 0.05) occurred after 40 min, and this increased pH was maintained for the remainder of the experimental period, corresponding to a serum cimetidine concentration of over 1.00 mg/l. Similarly, there was a significant rise (p less than 0.05) in serum gastrin concentration after 150 min. There was a significant direct correlation between corresponding measurements of intragastric pH and serum gastrin (p less than 0.001), between intragastric pH and serum cimetidine (p less than 0.001), and between serum gastrin and serum cimetidine (p less than 0.05). Ingestion of cimetidine results in an increase in the serum gastrin concentration in healthy subjects, presumably as a result of reduced secretion of acid in the stomach. Neither the endogenous increase in serum gastrin concentration nor the increase in intragastric pH causes alteration in the gastro-oesophageal sphincter pressure.