The Empirical Study on mtDNA4834 Deletion in Mimetic Aging Model Rat’s Cochlear / 听力学及言语疾病杂志

ABSTRACT

Objective To study the effect of Shenqiwan and vitamin E on mtDNA 4834 deletion in a mimetic aging rat model .Methods Forty rats three months old ,were randomly divided into four groups :group A ,which was treated with hypodermic 5 % D -galactose for 8 weeks ,and group B (shenqiwan group ,n=10) which was treated daily with Shenqiwan for 2 weeks after hypodermic 5 % D -galactose for 6 weeks ,group C (vitamin E group ,n = 10) which were treated daily with Vitamin E for 2 weeks after hypodermic 5 % D -galactose for 6 weeks ,group D were given saline only .Auditory brainstem response (ABR) was used to detect the hearing thresh-old of rats before and after the treatment .The inner ear tissue was harvested and mitochondrial DNA was amplified to identify the 4834 bp deletion mutation by nested primer polymerase chain reaction (nested PCR) technique .Re-sults The threshold of ABR in the group A ,B and C were significant higher than that in group D .However the difference in shift of ABR threshold between group A ,B ,C and group D was not significant .The mtDNA4834 de-letion rate in three modeled groups (group A ,B ,C) was significant high than that of in group D .There was statis-tically significant difference between the treated group (group B ,C) and the model group (group A) on mtDNA4834 deletion in cochlea ,but the difference between the treated groups on mtDNA 4834 deletion in cochlea was not statistically significant .Conclusion Shenqiwan and vitamin E can reduce the aging induced mtDNA 4834 deletion in aging rats inner ear .