吸入氧化亚氮对大鼠耳蜗总RNA产量的影响

Effects of N_2O inhalation on yield of total RNA in cochleas of the rats

目的通过检测氧化亚氮对大鼠耳蜗总RNA产量的影响,探讨氧化亚氮(N_2O)对大鼠内耳损伤的机制。方法将30只健康Wistar大鼠随机等分为3组:A组(对照组,n=10)持续吸入50%O_2 3 h;B组(实验组,n=10)持续吸入50%N_2O+50%O_2 3 h;C组(实验组,n=10)持续吸入50%N_2O+50%O_2 6 h。联用TRIzol和RNeasy法分别抽取3组大鼠耳蜗的总RNA,用分光光度法测总RNA的产量及电泳检测其质量。结果A组大鼠耳蜗得到总RNA 7.69μg;B组大鼠耳蜗得到总RNA 6.51μg,与A组比较减少15%;C组大鼠耳蜗得到总RNA 5.32μg,与A组比较减少31%。A_(260)/A_(280)值分别为2.07、2.04和2.05,提示RNA纯度高,电泳结果提示总RNA无降解。结论长时间吸入N_2O的大鼠耳蜗总RNA较正常大鼠耳蜗总RNA产量降低,提示N_2O干扰耳蜗RNA产量可能是造成耳损害的原因之一。

Objective To explore the mechanism of hearing impairment by N2O by testing the effects of N2O on yield of total RNA of cochleas of the rats. Methods Thirty Wistar rats were randomly divided into 3 groups as follows： group A （control group,n = 10） ,endlessly inhal/ng 50%O2 endlessly for 3 h; group B （ experimental group, n = 10）, endlessly inhaling 50% N2O ＋ 50% O2 for 3 h ; group C （ experimental group,n = 10） , endlessly inhaling 50% N2O ＋ 50%O2 for 6 h. Then the cochlear materials from 3 groups of rats were pooled and homogenized, and total RNA was extracted from the homogenized tissues by TRIzol method in combination with RNeasy method. Spectrophotometric analysis was used to determine the yield and purity of total RNA and gel electrophoresis was used to test whether there existed RNA degeneration. Results Total RNA extracted from groups A,B and C was 7.69,6.51 and 5.32 μg respec- tively. The results of spectrophotometric analysis showed the values of A260/A280 in groups A, B and C were 2.07,2.04 and 2.05 respectively. Gel electrophoresis revealed total RNA had no degeneration. Conclusion N2O could significantly inhibit the yield of total RNA in cochleas of the rats. The change in total RNA during anesthesia induced by N2O suggests it plays an important role in N2O -induced hearing impairment.