4. Discussion. This study showed that IV bolus injection of sulfated gastrin- 34 increased the levels of ghrelin in plasma in a dose-dependent manner in cattle. The results were, in general, in agreement with those obtained earlier in fasted rats I10.20]. However, gastric microdialysis and abdominal studies that human had effect on the of in 178l Lippi et al. 117lshowed that gastrin-17 inhibited isolated rat vagally prestimulated ghrelin release in the between earlier Some factors may account for the discrepancy that results and the present data. On important factor ferent forms of gastrin tide were administered. In the present study, bovine sulfated gastrin-34 and -17 were effective in the stimulation of ghrelin in cattle. However, human Leu15-gastrin- 17, which has a different N-terminal amino acid sequence from rat gastrin, showed no effect on ghrelin secretion in rats. Other factors such as of administration, doses of peptide, and feed routes ing conditions, may have influenced the results. The duration of increment of ghrelin was long in the high dose of gastrin injected group (Fig. 3A and