Effects of intermittent hypoxia on dielectric properties of rat gastrocnemius / 中国应用生理学杂志

ABSTRACT

<p><b>AIM</b>To study the changes in dielectric properties of gastrocnemius isolated from rats subjected to intermittent hypoxia for 4 weeks at the frequency range of 40 Hz - 110 MHz.</p><p><b>METHODS</b>Hypoxia was simulated by low-pressure chamber in male Sprague-Dawley rats, the rats were divided into two groups, that is, 4 weeks of intermittent hypoxia group and its control. The AC impedance of isolated gastrocnemius is measured with the Agilent 4294A impendance analyzer, and effects of intermittent hypoxia on dielectric properties of cells in isolated rat sural muscle were monitored by analyzing the dielectric numerical characters of the dielectric spectroscopy, the Cole-Cole plots, spectrum of loss factor and conductivity imaginary part, as well as loss tangent.</p><p><b>RESULTS</b>Intermittent hypoxia could induce some changes, both relative permittivity (epsilon L, epsilon h) and permittivity increment deltaepsilon reduced, conductivity at low-frequency kappa L increased, conductivity at high-frequency kappa h reduced, and at the same time, the conductivity difference deltakappa also reduced. The characteristic frequency (f1, f2) increased. Peak of loss factor, the peak of conductivity imaginary part and the peak of loss tangent reduced.</p><p><b>CONCLUSION</b>Fall in dielectric properties and increase in the characteristic frequency in skeletal muscle were induced by intermittent hypoxic acclimation.</p>