The difference of mitochondrial DNA 4,834 bp deletion mutation in tissues of inner ear and kidney and skeletal muscle of rat / 临床耳鼻咽喉头颈外科杂志

ABSTRACT

OBJECTIVE@#To explore the difference of mitochondrial DNA 4,834 bp deletion mutation in tissues of inner ear, kidney and skeletal muscle and to discuss the possible mechanism of this kind of mutation in doxorubicin induced mtDNA 4,834 bp deletion mutation rat model.@*METHOD@#Twenty-eight Wistar rats were randomly divided into two groups, one was experimental group (18 rats), the other was the blank control group (10 rats). The rats of experimental group were treated with intraperitoneal injection doxorubicin (1 mg/kg) twice a week for 3 months. The blank controls received an equivalent volume of saline instead. The tissues of inner ear, kidney and skeletal muscle were harvested and the mitochondrial DNA 4,834 bp deletion mutation was detected by nested-PCR (nested polymers chain reaction) technique. The product of PCR was sequenced directly.@*RESULT@#Two rats of the experimental group and the blank group died during the experiment. The frequency of the mitochondrial DNA 4,834 bp deletion mutation of inner ear, kidney and skeletal muscle were 68.75% (11/16), 75.00% (12/16) and 100.00% (16/16) respectively. The difference of this kind of mutation between tissues of the inner ear and the skeletal muscle was statistic significance (P 0.05). None of the rats of the blank control group carry this kind of mitochondrial DNA mutation.@*CONCLUSION@#The mitochondrial DNA 4,834 bp deletion mutation could be induce by doxorubicin in rats, and a notable difference were found of the frequencies of this kind of mutation between tissues of the inner ear and the skeletal muscle. So it suggested that this kind of mitochondrial DNA common deletion mutation was tissue specific.