Differential expression of ghrelin mRNA according to anatomical portions of human stomach.

BACKGROUND/AIMS: The detailed ghrelin distribution on mRNA level in different anatomical portions of adult stomach and its association with plasma ghrelin levels are not yet well established. We investigated the ghrelin mRNA and peptide expression in different anatomical portions of stomach in human adults.

METHODOLOGY: Stomach tissue samples were obtained from 16 patients with gastric cancer who underwent total gastrectomy. The normal stomach tissues were taken from the upper (gastric fundus and upper body), middle (gastric middle and lower body) and lower (gastric antrum and pylorus) portions of stomach, respectively. The expression of ghrelin mRNA and peptide in stomach tissue samples were measured using RT-PCR and immunohistochemistry.

RESULTS

The ghrelin/actin ratio was 0.78 (range 0-3.38; n=16) at the upper portion, 0.20 (range 0-1.28; n=16) at the middle portion and 0.07 (range 0-0.67; n=16) at the lower portion of the stomach (p=0.001). Ghrelin-positive cells were seen in all parts of the gastric mucosa and were most numerous in the glandular compartment compared to foveolar compartment. Gastric body or fundic mucosa showed ghrelin-positive cells most abundantly as compared to other portions of the gastric mucosa (p<0.001).

CONCLUSIONS

Ghrelin mRNA expression and immunoreactivity is highest at the upper portion of the human stomach.