Effects of in Vivo Administration of Pentagastrin, Secretin, and 13-Nle-Motilin on the in Vitro Incorporation of ¹⁴C-Leucine into Protein of Human Gastric Mucosa

Abstract

Mitznegg, P., Domschke, W., Domschke, S., Belohlavek, D., Sprügel, W., Strunz, U., Wünsch, E., Jaeger, E. & Demling, L. Effects of in vivo administration of pentagastrin, secretin, and 13-nle-motilin on the in vitro incorporation of ¹⁴C-leucine into protein of human gastric mucosa. Scand. J. Gastroent. 1976, 11, 657-660

Under endoscopic control, biopsy specimens were taken from the oxyntic gland area of the stomach before and after administration of pentagastrin, synthetic secretin, and 13-norleucine motilin (13-nle-motilin), respectively. In 29 volunteers, the basal rate of ¹⁴C-leucine incorporation into mucosal protein averaged 41.2 ± 7.7 × 10³ cpm/mg protein (mean ± S.D.). One and 4 hours after s.c. administration of pentagastrin (6 µg/kg body weight), values were significantly increased (p<0.05) by 18.9 and 21.8 %, respectively, with respect to the basal level. One hour after an intravenous shot of 2 CU per kg body weight of secretin, gastric mucosal protein synthesis was not substantially inhibited, whereas a 1-hour continuous i.v. infusion of 13-nle-motilin (0.4 μg/kg body weight, hr) significantly decreased ¹⁴C-leucine incorporation rates by 17.5% (p<0.05). In contrast to rats, 1 hour after s.c. pentagastrin, protein synthesis in human duodenal mucosa was not altered. From these results it may be concluded that pentagastrin has a trophic influence on gastric mucosa in man. Moreover, the data presented are compatible with the hypothesis that gastrin and motilin may be involved in the regulation of human gastric mucosal protein synthesis.

Key-words::

• Gastric mucosa
• man
• 13-nle-motilin
• pentagastrin
• protein synthesis
• secretin