Lower esophageal sphincter pressure, acid secretion, and blood gastrin after coffee consumption.

This study tested the hypothesis that differences in the processing of raw coffee beans can account for some of the variability in gastric effects of coffee drinking. Coffees were selected to represent several ways that green coffee beans are treated, ie, processing variables. These included instant and ground coffee processing, decaffeination method (ethyl acetate or methylene chloride extraction), instant coffee processing temperature (112 degrees F or 300 degrees F), and steam treatment. Lower esophageal sphincter pressure, acid secretion, and blood gastrin was measured in eight human subjects after they consumed each of the different coffees. Consumption of coffee was followed by a sustained decrease in lower esophageal sphincter pressure (P less than 0.05) except for three of the four coffees treated with ethyl acetate regardless of whether or not they contained caffeine. Caffeinated ground coffee stimulated more acid secretion that did decaf ground coffees (P less than 0.05), but not more than a steam-treated caffeinated coffee. Instant coffees did not differ in acid-stimulating ability. Ground caffeinated coffee resulted in higher blood gastrin levels than other ground coffees (P less than 0.05). Freeze-dried instant coffee also tended toward higher gastrin stimulation. It is concluded that some of the observed variability in gastric response to coffee consumption can be traced to differences in how green coffee beans are processed.

Association of infection due to Helicobacter pylori with specific upper gastrointestinal pathology.

The association of infection with Helicobacter pylori and antral (type B) gastritis now is clear, and the development of sensitive and specific serologic assays for IgA and IgG allows for diagnosis of this infection by noninvasive means. With use of these assays, we studied the association of infection with H. pylori and four other upper gastrointestinal inflammatory conditions: Barrett's esophagus, pernicious anemia (which accompanies type A gastritis), and duodenal and gastric ulcers. H. pylori was present in only 39% of 41 patients with Barrett's esophagus whose gastric biopsy specimens were examined histologically. Each serologic assay correctly categorized 39 (95.1%) of the 41 patients. For both assays the frequency of seropositivity noted for 58 patients with Barrett's esophagus was not different from that noted for age- and sex-matched healthy controls. Among 40 patients with pernicious anemia, the results of assays for IgA and IgG were positive for 17.5% and 0%, respectively; these prevalences were significantly less than the 50% (IgA) and 40% (IgG) positivities noted for matched controls (P less than .01 for each; McNemar's test). Among 57 patients with documented duodenal or gastric ulcers, the results of assays for IgG and IgA were positive for 100% and 98.2%, respectively; these prevalences were significantly higher than the rate noted for matched controls (P less than .001 for duodenal ulcers and P = .02 for gastric ulcers for IgA assay). These data suggest that infection with H. pylori is strongly associated with duodenal and gastric ulcers, negatively associated with pernicious anemia, and independent of Barrett's esophagus.

U.S. experience with omeprazole in duodenal ulcer. Multicenter double-blind comparative study with ranitidine. The Omeprazole DU Comparative Study Group.

To assess the comparative efficacy of omeprazole 20 mg, a proton pump inhibitor, versus ranitidine 150 mg twice a day, an H2-receptor antagonist, in healing duodenal ulcers we performed a randomized, double-blind, multicenter trial in 309 patients with endoscopically diagnosed ulcers. Patients were treated for up to four weeks and were seen at week 2 and at week 4, if unhealed at week 2, for determination of ulcer status by endoscopy, review of daily self-assessment symptom diaries, and clinical laboratory including fasting serum gastrin. Gastrin levels were repeated two weeks after cessation of study medication. Evaluation of baseline demographic and laboratory parameters demonstrated no significant differences between the two groups at entry. At week 2, 42% of the omeprazole and 34% of the ranitidine-treated patients were healed (P = NS). At week 4, there was a 19% advantage in ulcer healing for the omeprazole-treated patients in comparison to those treated with ranitidine (82% vs 63%, respectively, P less than 0.05). Healing of ulcers greater than or equal to 1.0 cm occurred in 83% of those treated with omeprazole versus 37% treated with ranitidine (P less than 0.01). There were no significant differences in rate of pain relief or incidence of clinical laboratory abnormalities. Mean fasting serum gastrin value during treatment increased over the baseline in both groups, (P less than 0.05). The percent change was significantly greater with omeprazole but few patients had elevations above the upper limit of normal for the assay. Both drugs were well tolerated. Omeprazole 20 mg demonstrated superiority in healing duodenal ulcers at four weeks in comparison to ranitidine 150 mg twice daily and was more effective in healing ulcers greater than or equal to 1.0 cm.

A randomized study of maintenance therapy with ranitidine to prevent the recurrence of duodenal ulcer.

After an active duodenal ulcer has healed in response to medical therapy, the rate of recurrence during the subsequent year is relatively high. We therefore enrolled 140 patients with healed duodenal ulcers in a two-year randomized, double-blind trial comparing maintenance therapy (ranitidine, 150 mg nightly) with placebo for the prevention of recurrent duodenal ulceration. We performed endoscopy annually and when symptoms suggested the recurrence of ulcers. Verified recurrent ulcers in either group were treated for four or eight weeks with open-label ranitidine (150 mg twice a day). Patients whose ulcers healed within eight weeks resumed randomized treatment. Prophylactic therapy with ranitidine reduced the rate of ulcer relapses from 63 percent in the placebo group to 37 percent in the ranitidine group (P less than 0.05). Treatment with ranitidine extended the median ulcer-free interval from one to two years (P less than 0.05). The first recurrences of ulcer were asymptomatic in half the ranitidine group and in a quarter of the placebo group. Prophylactic therapy with ranitidine also reduced the frequency of recurrent ulcers that were unhealed by eight weeks, that were bleeding, that were in the stomach, or that were the second recurrent ulcer within six months, from 43 percent in the placebo group to 21 percent. Patients who drank alcohol, smoked, had a history of ulcer disease, or had duodenal scarring or erosion at the time of entry into the study were at the greatest risk for recurrence and benefited the most from prophylactic ranitidine. We conclude that prophylactic treatment with ranitidine is effective in preventing the recurrence of duodenal ulceration.

Reduction in index of oxygen saturation at margin of active duodenal ulcers may lead to slow healing.

This study tested the hypothesis that reduced perfusion of a duodenal ulcer margin (ie, the mucosa 1-2 mm from the edge of the ulcer base) is associated with slow healing. Reflectance spectrophotometric measurement of indices of mucosal hemoglobin concentration (IHB) and mucosal hemoglobin oxygen saturation (ISO2) were obtained endoscopically in 21 patients at the ulcer margin and the adjacent mucosa (ie, the mucosa 1-2 cm from the edge of the ulcer base). In 17 patients with adequate follow-up, stepwise multilinear regression analysis revealed a significantly negative correlation (r = -0.69, P less than 0.05) between ISO2 at the ulcer margin minus ISO2 at the adjacent mucosa (delta ISO)2 and ulcer healing time. In addition, smoking, being black, and early relapse since the last ulcer attack were found to be associated with increased duration required for healing. The results of this pilot study suggest factors, in addition to smoking, that may have to be considered in future studies concerned with duodenal ulcer healing.

Characterization of the effects of neurokinins on canine antral muscle.

The excitation of longitudinal antral muscle by substance P (SP) involves both a myogenic and a cholinergic effect. To examine if these responses are mediated by different neurokinin receptors, we studied the mechanical response and the release of [3H]acetylcholine from antral muscle strips in response to SP, substance P methylester (SPME), neurokinin A (NKA), neurokinin B (NKB), and several non-mammalian tachykinins. All peptides studied showed a dose-dependent inotropic and chronotropic effect on spontaneous phasic contractions. This ionotropic effect in longitudinal muscle was partially atropine sensitive for SPME, SP, and NKB but not for NKA, whereas neither atropine nor tetrodotoxin had an effect in circular muscle. In longitudinal muscle, all three neurokinins were equipotent. In longitudinal muscle treated with atropine and in circular muscle, the rank order of potency for the inotropic response was NKA greater than NKB greater than SP greater than SPME. For the chronotropic response the rank order was SPME, SP greater than NKA greater than NKB. NKA, NKB, and SP caused a dose-dependent, tetrodotoxin-sensitive increase in [3H]acetylcholine release from strips preincubated with [3H]choline. NKA was significantly more potent to release [3H]acetylcholine than either NKB or SP. The stimulated release was inhibited by [D-Ala2,D-Met5]methionine enkephalinamide and the SP antagonist, spantide. These results are consistent with the hypothesis that NKA is the natural ligand mediating the myogenic inotropic response in both muscle layers and the cholinergic response in longitudinal muscle.

Somatostatin modulates cholinergic neurotransmission in canine antral muscle.

Somatostatin has been shown to inhibit antral motility in vivo. To examine the effect of somatostatin on cholinergic neurotransmission in the canine antrum, we studied the mechanical response of and the release of [3H]acetylcholine from canine longitudinal antral muscle in response to substance P, gastrin 17, and electrical stimulation. In unstimulated tissues, somatostatin had a positive inotropic effect on spontaneous phasic contractions. In tissues stimulated with substance P and gastrin 17, but not with electrical stimulation, somatostatin inhibited the phasic inotropic response dose dependently. This inhibitory effect was abolished by indomethacin. Somatostatin stimulated the release of prostaglandin E2 radioimmunoreactivity, and prostaglandin E2 inhibited the release of [3H]acetylcholine induced by substance P and electrical stimulation. Somatostatin increased the release of [3H]acetylcholine from unstimulated tissues by a tetrodotoxin-sensitive mechanism but inhibited the release induced by substance P and electrical stimulation. These results suggest that somatostatin has a dual modulatory effect on cholinergic neurotransmission in canine longitudinal antral muscle. This effect is excitatory in unstimulated tissues and inhibitory in stimulated tissues. The inhibitory effect is partially mediated by prostaglandins.

Gastroduodenal mucosal hemodynamics by endoscopic reflectance spectrophotometry.

The reflectance spectrophotometric technique measures an index of mucosal hemoglobin concentration and an index of oxygen saturation by spectral analysis of light reflected from the mucosal surface. Using a commercially available unit, a technique for obtaining reproducible endoscopic measurements with acceptable intraobserver and interobserver variability was developed in the anesthetized dogs. The reflectance spectrophotometric finding that experimentally induced prehepatic portal hypertension did not affect gastric mucosal blood flow was confirmed by hydrogen gas clearance measurements. Endoscopic studies in patients with active duodenal ulcer disease revealed a higher index of mucosal hemoglobin concentration and a normal index of oxygen saturation (i.e., an increase in blood flow) at the margin of the ulcer compared with the adjacent normal appearing mucosa.

The effect of an oral evening dose of nizatidine on nocturnal and peptone-stimulated gastric acid and gastrin secretion.

An evening oral dose of nizatidine, a new H2-receptor antagonist, was tested for its ability to suppress nocturnal gastric acid secretion and to inhibit food stimulated acid secretion the following day. Using a double-blind, randomized, cross-over design, nizatidine 30, 100, and 300 mg and placebo were compared in 8 male subjects with basal acid secretion greater than or equal to 3 mmol/h. Continuous nasogastric suction was started 2 h after oral dosing, and acid secretion was measured hourly overnight. Phenol red was used to determine the completeness of gastric aspiration. The following day, food stimulated acid secretion in response to 8% peptone meals was measured by intragastric titration to determine the carry-over effect of nizatidine. Serum gastrin levels were measured by RIA. Nizatidine inhibited overnight acid secretion in a dose-related manner with 30, 100, and 300 mg producing 57, 73, and 90% suppression. The effect was long-lasting, with nizatidine 300 mg decreasing acid secretion by 52% 10 h after administration. Peptone stimulated acid secretion on the following day was not inhibited by nizatidine. Gastrin levels did not differ significantly among the treatment groups. Nizatidine's effects on nocturnal acid secretion therefore resemble other H2-receptor antagonists.

Characterization of substance P effects on canine antral muscle.

Synthetic substance P increased the frequency and amplitude of spontaneously occurring contractions of circular and longitudinal muscle strips from canine gastric antrum in vitro. In longitudinal muscle, ED50 values calculated for frequency and amplitude were 3.7 X 10(-9) M and 9.7 X 10(-7) M, respectively. The effect of substance P on frequency in both layers and on amplitude in the circular layer was myogenic and unrelated to receptors for acetylcholine, norepinephrine, serotonin, histamine, and enkephalins. In the longitudinal muscle the amplitude response was partially inhibited by tetrodotoxin, atropine, and hexamethonium. The effect on amplitude but not on frequency was dependent on extracellular calcium. When compared to other stimulants of antral muscle contraction, the biological potency of substance P was higher than that of acetylcholine but significantly lower than that of gastrin and bombesin. Two putative substance P antagonists ([D-Pro2,D-Phe7,D-Trp9]substance P and [D-Pro2, D-Trp7,9]substance P) did not block the response of longitudinal muscle to substance P. Only the chronotropic response to substance P showed consistent, prolonged desensitization. These findings suggest that the mechanisms mediating the response to substance P in the canine antrum are different from other reported tissues.

Somatostatin inhibits gastric acid secretion after gastric mucosal prostaglandin synthesis inhibition by indomethacin in man.

The inhibitory effect of indomethacin, 200 + 200 mg administered per os over 24 hours, on the prostaglandin E2 generative capacity of gastric mucosal tissue was determined in healthy male volunteers. The effect of prostaglandin synthesis inhibition on somatostatin induced suppression of food-stimulated acid secretion was tested. Peptone meal stimulated acid secretion was quantified in five healthy volunteers by intragastric titration with and without indomethacin pretreatment. Somatostatin doses of 200, 400, and 800 pmol/kg/h each significantly inhibited the peptone stimulated acid output. Indomethacin treatment, resulting in 90% inhibition of prostaglandin E2 synthesis, did not affect glucose- or peptone-stimulated acid output or modify the inhibitory action of somatostatin. Clinically, acid inhibition by somatostatin has been used to treat bleeding peptic ulcers. Ulcer haemorrhage may be preceded by an excessive use of drugs that inhibit prostaglandin synthesis such as aspirin or other non-steroidal anti-inflammatory agents. Recent observations in the rat indicate that prostaglandins mediate the inhibitory action of somatostatin on gastric acid secretion. The present results suggest that prostaglandins are not required for inhibition of gastric acid secretion by somatostatin in man.

Sucralfate and cimetidine as single agents and in combination for treatment of active duodenal ulcers. A double-blind, placebo-controlled trial.

A randomized, double-blind, double-placebo study was conducted to compare the rates and predictors of healing in patients with endoscopically proved duodenal ulcers during treatment with sucralfate, cimetidine, or a combination of the two drugs. Standard therapeutic dosage regimens were used in each group. No antacids were allowed. Endoscopy was repeated at two weeks and, if needed, at four and eight weeks. Healing was defined as complete re-epithelialization of all ulcers. Cases in which there was a worsening of the ulcer or of symptoms were considered unhealed. Eight patients were dropped for protocol violations or unrelated medical illnesses; data from 61 patients were suitable for analysis. The healing rates achieved with sucralfate and cimetidine did not differ significantly at any time. However, the healing rate at two weeks for combination therapy (33 percent) was higher than for either sucralfate alone (15 percent) or cimetidine alone (10 percent). Cigarette smoking, a prior history of ulcer disease, and a low pepsinogen I to pepsinogen II ratio were significant predictors of delayed healing.

Approaches to the long-term treatment of duodenal ulcer disease.

Determining a course of long-term management for the patient with peptic ulcer disease requires an assessment of the severity of the disease, prior ulcer history (including complications, therapeutic intervention, and response to treatment), the predictors of the disease course, the degree of disability, and the available therapy (pharmacologic or surgical). A consideration of the predictors of the disease course that have been previously identified as useful in ulcer clinical trials (sex, age, acid secretory response, serum pepsinogen concentration, cigarette usage) and of ulcer-related disability (nutritional, emotional, job status) provides objective criteria to be entered into the long-term management decision.

Long-term follow-up of duodenal ulcer patients.

The CURE peptic ulcer clinic started in April 1974. Patients (mostly veterans) with documented ulcer disease were interviewed regularly and inpatient hospitalizations were reviewed for follow-up periods of up to 6 years. Data from 245 male ulcer patients, 190 with duodenal ulcer alone and 55 with both documented duodenal ulcer (DU) and gastric ulcer (GU), were analyzed to assess the natural history of ulcer disease and factors predicting the severity of its course. Eleven percent of clinic patients had a complication (bleeding requiring a transfusion, perforation, or obstruction) during follow-up. Complication rates were about 2.7% per year for those with no prior complication, and about 5% per year for those with a prior complication. No patient variables or ulcer markers were related to the likelihood of a complication. Patients with both DU and GU were similar to patients with DU alone on many background variables, but the combined ulcer group had a significantly higher frequency of blood group nonsecretors, increased incidence of cigarette smoking, and greater frequency of complications or ulcer hospitalization prior to entry into the study and during follow-up. These factors, together with our failure to find differences in aggressive factors (acid output and PGI), suggests that DU + GU represents a different disease entity marked by additional defects in mucosal defense.(ABSTRACT TRUNCATED AT 250 WORDS)

Healing of benign gastric ulcer with low-dose antacid or cimetidine. A double-blind, randomized, placebo-controlled trial.

We conducted a 12-week, double-blind, randomized, placebo-controlled trial to determine whether cimetidine (300 mg with meals and at bedtime) or a convenient, liquid aluminum-magnesium antacid regimen (15 ml one hour after meals and at bedtime) would expedite healing or relief of symptoms in patients with benign gastric ulcer. Of the 101 patients who completed the trial according to protocol, 32 received the antacid, 36 cimetidine, and 33 placebo. At 4, 8, and 12 weeks after entry, ulcers had healed in a larger percentage of patients treated with cimetidine than of those treated with placebo: 53, 86, and 89 per cent of the cimetidine group versus 26, 58, and 70 per cent of the placebo group (P = 0.02, 0.01, 0.05), respectively. Healing at the three intervals had occurred in 38, 70, and 84 per cent, respectively, of the antacid-treated patients. Neither cimetidine nor antacid was more effective than placebo in relieving symptoms. The presence or absence of symptoms during the fourth and eighth treatment weeks was a poor predictor of the presence of absence of an ulcer crater. We conclude that cimetidine significantly hastens the healing of benign gastric ulcer.

Antral gastrin concentration in gastric ulcer disease. The finding of high concentrations in a few patients.

Antral gastrin concentratin (AGC) was measured in forceps biopsy specimens of prepyloric mucosa obtained at endoscopy in 65 patients with various kinds of gastric ulcer and in 31 nonulcer control patients. AGC in 32 patients with a lesser curvature gastric ulcer, 10.0 +/- 2.0 (mean +/- 1 SE) ng gastrin/mg tissue was significantly less (P < 0.01) than AGC in 31 nonulcer control patients, 14.4 +/- 1.4. AGC was similar to the control values in 23 patients with a pyloric channel ulcer, 15.2 +/- 1.7; 5 patients with a greater curvature ulcer, 15.0 +/- 4.8; and 3 patients with both duodenal and gastric ulcers, 15.8 +/- 0.7. AGC was significantly greater (P < 0.01) than the control values in 3 patients with a vagotomy and pyloroplasty and a gastric ulcer, 29.8 +/- 5.0. In contrast with most lesser curvature gastric ulcer patients who had low AGC, 3 gastric ulcer patients had antral gastrin values which were about three times the mean AGC of the controls. Two of these patients had fasting serum gastrin values which were more than twice the mean control fasting serum gastrin. Meal-stimulated integraed gastrin responses in these 3 patients ranged from three to nine times the mean control response. These findings suggest that a high AGC may account for a few instances of increased serum gastrin concentrations in gastric ulcer patients.