亚磁场和模拟微重力复合环境对大鼠腓肠肌介电特性的影响(英文)

Effects of Hypo-magnetic Field and Simulated Microgravity on Dielectric Properties of Gastrocnemius in Rats

目的研究亚磁场和后肢去负荷对大鼠腓肠肌介电特性的影响。方法雄性SD大鼠24只分别在正常环境(Con),亚磁场环境(HMF),后肢去负荷环境(HLU)以及亚磁场和后肢去负荷复合环境(HMF+HLU)饲养4周。用阻抗分析仪在0.1 MHz到120 MHz频率范围内检测大鼠腓肠肌介电谱,用单项Cole-Cole方程对实验数据进行拟合,获得大鼠腓肠肌的介电参数。结果 1)HMF和HLU处理后腓肠肌的电导率增加,HMF组增加程度更高。2)介电常数的虚部和电导率的虚部受HMF或HLU作用后均减小。3)受HMF或HLU影响,特征频率移向高频。4)HMF作用后腓肠肌的κ0.1MHz值显著升高(P<0.05),尽管HLU处理后Δε降低12.8%,κ0.1MHz增加30.9%,但差异不具统计性。结论 HLU处理大鼠4周对大鼠腓肠肌介电特性无显著影响,与HLU作用相比,HMF的作用更强。

Objective To investigate the effects of hypo-magnetic field and hind-limb unloading on dielectric properties of rat gastrocnemius. Methods Twenty-four male Sprague-Dawley rats were devided into 4 groups to be treated under normal （ Con）, hypo-magnetic field （ HMF）, hind-limb unloading （HLU） and HMF ＋ HLU for 4 weeks. The dielectric spectra of gastrocnemius samples from each rat in different groups were detec- ted with an impedance analyzer at the frequency range from 0.1 MHz to 120 MHz. Then the dielectric parame- ters were estimated with the one-pole Cole-Cole equation to fit the experiment data. Results 1 ） the conduCtivi- ty of gastrocnemius increased in both HMF group and HLU group, and the increased degree in HMF group was higher than that in HLU group ; 2） the values of e＂ and K＂ decreased in HMF group and I-ILU group, but there was no significant change in HMF ＋ HLU group as compared with Con group; 3） the characteristic frequency was shifted to higher frequency in HMF group or HLU group, but not in HMF ＋ HLU group ; 4） the values of K0.1nHz significantly increased in HMF group （P 〈 0.05 ）. Although, the values of A8 decreased about 12.8% and K0 1MHz increased about 30.9% in HLU group, no significant change was observed in this study. Conclu- sion HLU treatment for 4 weeks was of no significant effect on the dielectric properties of rat gastrocnemius, however, the effect of HMF is more obvious than that of HLU.