Dielectric properties of hypothermic rat artery

The temperature and frequency dependencies of the dielectric parameters for the rat artery are used to analyse effects of hypothermia on this tissue. Measurements were performed over the frequency range 500 Hz to 100 kHz and at temperatures from 19 to 60 °C. The artery samples contained about 12% water by mass at room temperature at a relative humidity of 70%. The frequency dependencies of the loss tangent for the control, mild hypothermic and moderate hypothermic artery exhibit two peaks at 2 kHz and 35 kHz in the α-dispersion region. The results were discussed in terms of the distribution of relaxation frequencies and the activation energy for the conduction and polarization mechanisms particularly in the elastin–water and collagen–water systems. The knowledge about dielectric behavior of the hypothermic rat artery in vitro is important due to clinical application of local and systemic hypothermia.

The variation of ɛ″ as a function of ɛ′ for the control (□: 19 °C; ■: 50 °C), mild hypothermic (○: 19 °C; ●: 50 °C) and moderate hypothermic (▵: 19 °C; ▴: 50 °C) artery.Figure optionsDownload as PowerPoint slideHighlights
► We report effect of hypothermia on dielectric behavior of rat artery.
► Measurements were performed in the α-dispersion region.
► Experimental data are described by the Cole–Cole relation.
► Loss tangent is lower for hypothermic artery than for healthy one.