ABSTRACT
Objective To study the role of gastric mitochondrial DNA cytochrome C oxidases (COX) subunit Ⅱ gene and its expression in diabetic gastric motility dysfunction. Methods Seventy Wister rats were randomly divided into 2 groups: diabetic group (STZ 60mg/Kg intraperitonealy) and control group. The changes in expressions of COX protein were assayed by Westernblot. Mitochondrial DNA COX mRNA was assayed with reverse-transcriptional polymerase chain reaction(RT-PCR). Cytochrome C oxidase activity was determined by ultraviolet spectrophotometer. Results Gastricelectric dysrythmia was more frequently delected in diabetic rats, and the COX activity in diabetic rats was 0.41?0.21/min, which was significantly lower than that in normal rats (0.78?0.37/min). The expression of gastrointestinal COX protein and COX gene in diabetic gastroparesis rats were markedly decreased compared with normal rats. Conclusion Cytochrome C oxidases activity was greatly reduced in diabetic rats. Diabetic gastroparesis was associated with down-regulation of the expression of gastrointestinal mtDNA encoding COX gene and protein. These changes might play a key role in pathogenesis of diabetic gastroparesis
ABSTRACT
Objective To study the mechanism of cisapride in the treatment of gastricelectric dysrhythmia. Methods Cisarpride was gavage fed to rats in which gastricelectric dysrhythmia hed been reproduced. The cholinergic and nitriergic nerves in myenteric plexus of gastric antrum were examined with histochemical staining methods and whole mount preparation technique. The levels of cAMP and cGMP in the antral smooth muscle were measured by radioimmunoassay. Results Gastricelectric dysrhythmia in the model group was ameliorated after the treatment with cisapride(P