Search

The quantification of gastroduodenal motility uses invasive methods. The aim of our study was to further characterize the contractility of antrum, pylorus and duodenal bulb in two states, using a new, non invasive fluorographic method. Healthy volunteers (mean age = 28) were involved in this study under fasting conditions (n = 20) and after a meal (n = 20). In both conditions, the subjects have swallowed 250 ml of a barium sulfate solution for fluoroscopic gastrographies taken every 2 seconds, during 30 s. Spot films were analysed using a graphic table and locally developed microcomputer program to generate space-time diagrams of antral and duodenal areas and of pylorus diameters. For each subject, the antral CA, duodenal CB contractilities (maximal variation of antral, duodenal areas in p 100) and pylorus contractility CP (closure during the observation time in p 100) were calculated. CA values were high in the two situations, but did not differ (81.1 p 100 vs 82.5 p 100 post-prandial). In contrast, CP was higher under fasting (54.0 p 100) than in post-prandial (15.0 p 100; p less than .001). Two pyloric motor patterns were observed in post-prandial: A--pyloric contractions in relation with the end of antral contraction B--augmented pyloric resistances observed during the end of antral contraction and also associated with duodenal contractions. CB was low in post-prandial (27.0 p 100) compared to fasting CB (50.8 p 100; P less than .001). This method is reproducible and simple to use. It allows quantification of contractility and coordination in the antrum, pylorus and duodenal bulb. It may be useful to assess gastroduodenal motility under pathological conditions.

Early radiation toxicity is characterized by nausea and vomiting. We have previously shown that gastric emptying, gastric motility, and gastric secretion were suppressed after total body exposure to irradiation. In the present studies, we evaluated the relation between vomiting and gastric function in nine rhesus monkeys and explored the possible role of prostaglandins (PG) in these phenomena. The concentration of PG in plasma and gastric juice was determined using a standard radioimmunoassay and gastric acid output was measured concurrently using a marker dilution technique. The animals were studied in the basal state and after total body exposure to 800 cGy 60Co delivered at a rate of 500 cGy/min. Acid output was abolished from 40 min to 2 h after irradiation but had returned to preirradiation levels 2 days later. Plasma PGE2 and PGI2 (as measured by 6-keto-PGF1 alpha determination) were not significantly modified by irradiation. In contrast, irradiation produced an immediate significant increase (P less than 0.05) in gastric juice concentration of PGE2 (318 +/- 80 to 523 +/- 94 pg/ml; mean +/- SE) and PGI2 (230 +/- 36 to 346 +/- 57 pg/ml); both had returned to basal levels 2 days later. Thus, an increase in gastric juice concentration of both PGE2 and PGI2 is associated with the radiation induced suppression of acid output.

The velocities of gastric peristaltic waves were measured on fluorographic series made in normal subjects and patients with duodenal ulcer. After an overnight fast, the subjects drank 250 ml of barium suspension. Sequential radiograms were taken every 2 s during 30 s after two pyloric ejections. Peristaltic waves were located and their displacements measured with an Apple Graphic Tablet. Wave progression diagrams and velocity histograms were drawn for each subject. The velocities were calculated every 2 s. A "spread index" Ip was determined for each subject, characterizing the irregularity of propagation. Mean frequency and mean velocity were greater in duodenal ulcer patients (3.6 c/min; 3.7 mm/s) than in normal subjects (2.9 c/min; 2.4 mm/s; p less than 0.001). Nevertheless, no significant difference was found between proximal or midcorpus and antral velocities, in ulcer patients as well as in normal subjects, contrarily to classical data. However, the velocities were not uniform along the stomach. The contractions spread unevenly and displayed transient slopes. The irregularities of propagation were more pronounced in normal subjects, ranging from 0 to 14 mm/s with 28 p. 100 of velocities less than 1 mm/s, then in ulcer patients (0 to 13 mm/s with 12 p. 100 of low velocities). The spread index Ip was greater in normal (ranged from 0.54 to 2.62) than in ulcer patients (ranged from 0.16 to 0.48; p less than 0.001). This study showed that the propagation velocity of the peristaltic waves and its regularity were different in normal subjects and in duodenal ulcer patients.