Expression of GDNF in Gastric Wall of Slow Transit Constipation Rats and Effect of Exogenous GDNF

Background:Slow transit constipation(STC) is mainly characterized by colonic motility disorder,and exogenous glial cell line-derived neurotrophic factor(GDNF) can improve colonic motility.Many studies have shown gastric motility disorder in STC,however,the role of abnormal expression of GDNF in gastric wall on gastric motility disorder and the effect of exogenous GDNF have not been reported yet.Aims:To investigate the expression of GDNF in gastric wall in STC rats and the effect of exogenous GDNF.Methods:STC model was established by gastric infusion with rhubarb in rats.The rats were randomly divided into normal group,GDNF group,STC model group and STC model GDNF group. Rats in GDNF group and STC model GDNF group were injected with recombinant human GDNF into caudal vein,the rest groups were injected with 0.9%NaCl solution.After one week the rats were sacrificed,and the mRNA and protein expressions of GDNF in gastric wall were determined by RT-PCR and immunohistochemistry,respectively.Results:The expression of GDNF mRNA in gastric wall in STC model group was lower than that in STC model GDNF group and GDNF group(both P0.05).No significant difference of positive expression of GDNF in gastric wall was found between STC model GDNF group and STC model group(P0.05).Conclusions:Long term use of rhubarb can down-regulate the expression of GDNF in gastric wall in STC rats.Exogenous GDNF may improve the expression of GDNF.