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

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/s², 4 hours energy equivalent frequency-weighted acceleration, 3.03 m/s²), moderate(6.13 m/s²), and high(12.30 m/s²) 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.