Ghrelin improves delayed gastrointestinal transit in alloxan-induced diabetic mice.
OBJECTIVE
To investigate the effects of ghrelin on delayed gastrointestinal transit in alloxan-induced diabetic mice.


METHODS
A diabetic mouse model was established by intraperitoneal injection with alloxan. Mice were randomized into two main groups: normal mice group and diabetic mice group treated with ghrelin at doses of 0, 20, 50, 100 and 200 mug/kg ip. Gastric emptying (GE), intestinal transit (IT), and colonic transit (CT) were studied in mice after they had a phenol red meal following injection of ghrelin. Based on the most effective ghrelin dosage, atropine was given at 1 mg/kg 15 min before the ghrelin injection for each measurement. The mice in each group were sacrificed 20 min later and their stomachs, intestines, and colons were harvested immediately. The amount of phenol red was measured. Percentages of GE, IT, and CT were calculated.


RESULTS
Percentages of GE, IT, and CT were significantly decreased in diabetic mice as compared to control mice (22.9 +/- 1.4 vs 28.1 +/- 1.3, 33.5 +/- 1.2 vs 43.2 +/- 1.9, 29.5 +/- 1.9 vs 36.3 +/- 1.6, P < 0.05). In the diabetic mice, ghrelin improved both GE and IT, but not CT. The most effective dose of ghrelin was 100 mug/kg and atropine blocked the prokinetic effects of ghrelin on GE and IT.


CONCLUSIONS
Ghrelin accelerates delayed GE and IT but has no effect on CT in diabetic mice. Ghrelin may exert its prokinetic effects via the cholinergic pathway in the enteric nervous system, and therefore has therapeutic potential for diabetic patients with delayed upper gastrointestinal transit.
Qiu
Wen-Cai
WC
Department of General Surgery, The Affiliated Sixth Hospital of Medical School, Shanghai Jiaotong University, Shanghai 200233, China.
Wang
Zhi-Gang
ZG
Lv
Ran
R
Wang
Wei-Gang
WG
Han
Xiao-Dong
XD
Yan
Jun
J
Wang
Yu
Y
Zheng
Qi
Q
Ai
Kai-Xing
KX
D000818:Animals; D003106:Colon / Q000187:drug effects / Q000503:physiopathology; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D005746:Gastric Emptying / Q000187:drug effects*; D005772:Gastrointestinal Transit / Q000187:drug effects*; D054439:Ghrelin / Q000627:therapeutic use*; D007422:Intestines / Q000187:drug effects / Q000503:physiopathology; D051379:Mice; D008810:Mice, Inbred C57BL
D054439:Ghrelin