后肢接振对家兔脑及肌肉组织内皮素受体mRNA水平的影响

Effects on Endothelin Receptor mRNA Levels in Rabbits with Hind Legs Vibration

[目的]探讨后肢接振家兔内皮素受体(ETR)mRNA表达的影响。[方法]将32只新西兰大白兔随机分为低、中、高强度接振组(4 h等能量频率计权加速度分别为3.03、6.13、12.30 m/s2)和对照组,对各强度组家兔进行接振实验,共45 d。接振实验结束后,取各组家兔脑组织及肌肉组织,应用实时荧光定量PCR技术检测各组家兔组织中ETR-A mRNA、ETR-B mRNA的表达量。[结果]接振实验后低、中、高强度组脑组织ETR-A mRNA、ETR-B mRNA的表达量分别为8.31±4.78、40.07±24.84,30.62±16.33、212.58±74.49和54.01±27.64、341.42±203.73,骨骼肌ETR-A mRNA、ETR-B mRNA的表达量分别为1.40±0.56、2.51±1.14,2.06±1.89、0.79±0.87和0.85±0.16、1.44±0.68。各强度组家兔骨骼肌组织、脑组织ETR mRNA表达总体上增高(P<0.05,P<0.01)。与对照组比较,3个强度组脑组织ETR-A mRNA、ETR-B mRNA表达均增强(P<0.01);骨骼肌组织中,中强度组的ETR-A mRNA及低强度组ETR-B mRNA的表达增强(P<0.05,P<0.01)。[结论]后肢接振可致家兔ETR mRNA表达升高。振动性血管损伤和神经损伤的发生,可能是内皮素等缩血管物质与其受体水平上调共同作用的结果。

[ Objective ] To examine the effects on endothelin receptor （ETR） mRNA levels in rabbits exposed to hind legs vibration. [ Methods ] Thirty-two New Zealand white rabbits were randomly divided into low （3.03 m/s^2, 4 hours energy equivalent frequency-weighted acceleration, 3.03 m/s^2）, moderate （6.13 m/s^2）, and high （12.30m/s^2） intensity groups and control group. All the exposure groups recieved vibration loading test for 45 d. After that, the ETR-A and ETR-B mRNA expressions of muscle tissue and brain tissue were measured by real-time fluorescent quantitative PCR. [ Results ] After the vibration loading test, the expression levels of ETR-A mRNA and ETR-B mRNA in brain tissue were 8.31 ± 4.78 and 40.07 ± 24.84 in the low intensity group, 30.62 ±16.33 and 212.58 ± 74.49 in the moderate intensity group, and 54.01 ±27.64 and 341.42± 203.73 in the high intensity group, respectively, and the expression levels in muscle tissue were 1.40 ± 0.56 and 2.51 ±1.14 in the low intensity group, 2.06 ± 1.89 and 0.79 ± 0.87 in the moderate intensity group, and 0.85 ± 0.16 and 1.44 ± 0.68 in the high intensity group, respectively. The expression levels of ETR mRNA in both muscle and brain tissues of the rabbits in each group were elevated significantly （P〈0.05, P 〈 0.01）. The expression of ETR-A mRNA and ETR-B mRNA in brain tissues of the three intensity groups increased statistically compared with the control group （P 〈 0.01）; in muscle tissues the expression level of ETR-A mRNA in the moderate intensity group and the expression level of ETR-B mRNA in the low intensity group were higher than those in the control group （P〈0.05, P〈0.01）. [ Conclusion ] Vibration loaded to hind legs could induce increased expression of ETR mRNA in muscle and brain tissues of rabbits, which might result in vascular and nervous impairments.