Study on the changes in gastric cytochrome C oxidases gene Ⅱ and its expression in diabetic rats / 解放军医学杂志

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