[Comparative study of the gastric emptying of disaccharides and their respective monosaccharides in rats with ontogenic lactase deficiency].

In order to evaluate the gastric emptying of disaccharides and their monosaccharides, 64 male, Wistar rats weighing approximately 180 g, were divided into the following eight groups containing eight animals each: maltose, sucrose, lactose, and lactulose, and their correspondent group of monosaccharides: glucose, fructose plus glucose, galactose plus glucose and galactose plus fructose. Each animal received, after a 20 hours fast, 2 ml/100 g weight of a test meal containing a 10% solution of the correspondent sugar and phenol red (6 mg/dl) as a marker. Gastric retention was determined at 10 minutes after orogastric infusion and expressed as a percentage of the infused volume. The observed values (mean +/- SE) of gastric retention (%) of sucrose (35.0 +/- 1.8), lactose (30.4 +/- 1.5), and lactulose (29.5 +/- 1.6) were significantly lower (t test alpha = 0.05), than those observed with their respective monosaccharides, i.e. glucose plus fructose (46.9 +/- 2.6), glucose plus galactose (48.3 +/- 2.4), galactose plus fructose (43.5 +/- 1.5). No difference was noted between gastric retention of maltose (49.9 +/- 4.7) and that of glucose (53.0 +/- 3.0). As far the disaccharides are concerned, statistical analysis (ANOVA followed by Tukey test alpha = 0.05) revealed no differences among the values of gastric retention of sucrose, lactose and lactulose. Gastric retention of maltose was significantly greater than that of the other disaccharides. No differences were found among the gastric retention of monosaccharides.(ABSTRACT TRUNCATED AT 250 WORDS)