Effect of aspirin and indomethacin on epidermal growth factor secretion in duodenal tissue fragments cultivated in vitro.

The aim of the present study was to determine the effect of aspirin and indomethacin on epidermal growth factor (EGF) secretion in duodenal tissue fragments cultivated in vitro. The fragments were obtained from healthy subjects by gastroscopy, cultured in McCoy's medium and gassed with 95% O2 and 5% CO2 at 37 degrees C. After an incubation of 30 min, the culture medium was decanted, and the quantity of hormone determined by radioimmunoassay. The mean EGF level detected in the medium was 10.94 ng/mg protein tissue. The addition of aspirin (final concentration 10(-7) M) to the medium reduced mean EGF levels to 7.5 ng/mg (p less than 0.05), whereas aspirin 10(-8) M did not produce such a modification. The addition of indomethacin (final concentration 10(-8) M) decreased mean EGF levels to 5.37 ng/mg (p less than 0.001). In all experimental conditions, the addition of anti-somatostatin (SRIF) antibodies determined a remarkable increase in EGF (p less than 0.01). The results of this study show aspirin and indomethacin to be direct, not SRIF-mediated inhibitors of EGF release.