JEJUNAL GLUCOSE-ABSORPTION IS ENHANCED BY EPIDERMAL GROWTH-FACTOR IN MICE

The effects of epidermal growth factor on intestinal glucose transport were examined in mice. Glucose transport measurements were performed using an in vitro assay system that estimated the rate of accumulation of [H-3]3-O-methyl-D-glucose. In Experiment 1, two-mo-old male and fe male mice were subcutaneously injected once daily with 0, 150 of 300 m u g epidermal growth factor/kg body weight for 3 d. Jejunal glucose ac tive transport was increased in a dose-dependent manner. There were no gender-related differences in intestinal glucose transport or the res ponse to exogenous epidermal growth factor. In Experiment 2, 2-, 10- a nd 18-mo-old mice were administered 0 or 300 mu g epidermal growth fac tor/kg body weight using a treatment similar to that used in Experimen t 1. Active intestinal glucose transport was 30% greater in response t o epidermal growth factor in each of the three age groups. Ouabain-sen sitive and -insensitive jejunal oxygen consumption was increased in re sponse to epidermal growth factor such that total jejunal respiration was stimulated 15 to 31%. The epidermal growth factor related percenta ge increase in glucose absorption was similar to the percentage increa se in oxygen consumption such that the apparent energetic efficiency o f glucose transport was unaffected. In both experiments, the active co mponent of glucose transport was increased by epidermal growth factor while passive transport was not affected. Jejunal morphology and mucos al DNA and protein concentration were not altered by epidermal growth factor treatment. Epidermal growth factor-induced increases in intesti nal absorption was not attributable to mucosal hyperplasia.