Effect of different fasting stages on ghrelin expression in stomach of rats fed with routine or high-fat diet

Objective To study the effect of different fasting stages and long term high-fat diet on ghrelin expression in rat stomach. Methods Northern blot was applied to detect ghrelin expression in gastric tissue during different fasting stages in rats fed with routine or high-fat diet. Results The expression of ghrelin in routine diet group was elevated during short-period fasting (≤72 h)(24 h P0.05, 72 h P0.01), but descended during long-period fasting (120 h) (P0.01). However, different fasting stages had no effect on the expression of ghrelin in high-fat diet group. Besides, the expression of ghrelin in high-fat diet group was much lower than that in routine diet group when rats were not fasted (P0.01). Conclusion The expression of ghrelin in routine diet group is initially elevated, then decreased. The expression of ghrelin in high-fat diet group does not change during various fasting stages. The decreased expression of ghrelin in high-fat diet group seems to be one of the mechanisms that body spontaneously reduces appetite to control its own body weight.