Ectopic expression of ghrelin affects gastric H(+)-K(+)-ATPase activity and expression of GHR/IGF-1 system in weaned mice.

OBJECTIVES

Ghrelin has been implicated in the regulation of gastric growth and functional development, but it is yet to be determined whether and how ghrelin over-expression may modify gastric growth, gastric acid secretion and mRNA expression of other gastric endocrine hormones. 25-day-old mice were injected intramuscularly with vacant plasmid (VP) or recombinant plasmid expressing secretory ghrelin at the doses of 50μg (LG) and 100μg (HG).

RESULTS

Expression of ghrelin mRNA was detected in muscles 15days post-injection, being most abundant in HG mice. In accordance with the ghrelin expression, gastric weight increased (P<0.05) in HG mice, compared with VP control group. Significant increase of gastric mucosa H(+)-K(+)-ATPase mRNA expression was detected in HG mice compared to VP control group (P<0.05). Compared with VP mice, gastric somatostatin (SS) mRNA expression decreased in LG and HG mice (P<0.05), while gastric gastrin expression had no significant difference.

CONCLUSIONS

I.M. injection of plasmid encoding ghrelin improved gastric growth and gastric acid secretion with decreased SS mRNA in weaned mice.