Changes in electrical resistivity of swine liver after occlusion and postmortem

The resistivity of swine liver tissue was measured in vivo, during induced ischaemia and post-mortem, so that associated changes in resistivity could be quantified. Plunge electrodes, the four-terminal method and a computer-automated measurement system were used to acquire resistivities between 10 Hz and 1 MHz. Liver resistivity was measured in vivo in three animals at 11 locations. At 10 Hz, resistivity was 758±170 Ω·cm. At 1 MHz, the resistivity was 250±40Ω·cm. The resistivity time course was measured during the first 10 min after the liver blood supply in one animal had been occluded. Resistivity increased steadily during occlusion. The change in resistivity of an excised tissue sample was measured during the first 12h after excision in one animal. Resistivity increased during the first 2h by 53% at 10 Hz and by 32% at 1MHz. After 2h, resistivity decreased, probably owing to membrane breakdown. The resistivity data were fitted to a Cole-Cole circle, from which extracellular resistance Re, intracellular resistance Ri and cell membrane capacitance Cm were estimated. Re increased during the first 2h by 95% and then decreased, suggesting an increase in extracellular volume. Cm increased during the first 4h by 40%, possibly owing to closure of membrane channels, and then decreased, suggesting membrane breakdown. Ri stayed constant during the initial 6h and then increased.

[1]  K. Foster,et al.  Dielectric properties of mammalian tissues from 0.1 to 100 MHz: a summary of recent data. , 1982, Physics in medicine and biology.

[2]  R. Bragos,et al.  Changes in myocardial impedance spectrum during acute ischemia in the in-situ pig heart , 1996, Proceedings of 18th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[3]  J. A. Bushman,et al.  Medical & biological engineering & computing , 2006, Medical and Biological Engineering and Computing.

[4]  Michel Bourdages,et al.  Monitoring living tissues by electrical impedance spectroscopy , 1994, Annals of Biomedical Engineering.

[5]  P. Hegarty,et al.  Evidence for a relationship between ATP hydrolysis and changes in extracellular space and fibre diameter during rigor development in skeletal muscle. , 1974, Comparative biochemistry and physiology. A, Comparative physiology.

[6]  A. Surowiec,et al.  Radiofrequency dielectric properties of animal tissues as a function of time following death. , 1985, Physics in medicine and biology.

[7]  S. Rush,et al.  Resistivity of Body Tissues at Low Frequencies , 1963, Circulation research.

[8]  J. Farber,et al.  Myocardial ischemia: the pathogenesis of irreversible cell injury in ischemia. , 1981, The American journal of pathology.

[9]  Kenneth R. Foster,et al.  The dielectric properties of canine and normal and neoplastic splenic tissues , 1988, Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference.

[10]  T Iritani,et al.  Electrical properties of extracted rat liver tissue , 1995, Research in experimental medicine. Zeitschrift fur die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie.

[11]  J. G. Webster,et al.  Impedance of Skeletal Muscle from 1 Hz to 1 MHz , 1984, IEEE Transactions on Biomedical Engineering.

[12]  H. Schwan,et al.  Die elektrischen Eigenschaften von Muskelgewebe bei Niederfrequenz , 1954 .

[13]  Eung Je Woo,et al.  Dependence of apparent resistance of four-electrode probes on insertion depth , 2000, IEEE Transactions on Biomedical Engineering.

[14]  M. Bassi,et al.  ULTRASTRUCTURAL CYTOPLASMIC CHANGES OF LIVER CELLS AFTER REVERSIBLE AND IRREVERSIBLE ISCHEMIA. , 1964, Experimental and molecular pathology.

[15]  L. Geddes,et al.  The specific resistance of biological material—A compendium of data for the biomedical engineer and physiologist , 1967, Medical and biological engineering.

[16]  N. Gilula,et al.  The Gap Junction Communication Channel , 1996, Cell.

[17]  T. Ryan,et al.  Tissue impedance as a function of temperature and time. , 1996, Biomedical sciences instrumentation.

[18]  J. Gallis,et al.  Phosphorus-31 nuclear magnetic resonance of isolated rat liver during hypothermic ischemia and subsequent normothermic perfusion. , 1992, Journal of hepatology.

[19]  H. Schwan,et al.  Biological Engineering , 1970 .

[20]  Francis A. Duck,et al.  Physical properties of tissue : a comprehensive reference book , 1990 .

[21]  J. Revel,et al.  Intercellular communication in normal and regenerating rat liver: a quantitative analysis , 1981, The Journal of cell biology.

[22]  C Gabriel,et al.  The dielectric properties of biological tissues: I. Literature survey. , 1996, Physics in medicine and biology.

[23]  Anistropy and Postmortem Changes in the Electrical Resistivity and Capacitance of Skeletal Muscle , 1980 .

[24]  J. D. Munck,et al.  The electric resistivity of human tissues (100 Hz-10 MHz): a meta-analysis of review studies. , 1999, Physiological measurement.

[25]  J. Schellens,et al.  Gap junction ultrastructure in rat liver parenchymal cells after in vivo ischemia , 1987, Virchows Archiv B Cell Pathology Including Molecular Pathology.

[26]  P. Steendijk,et al.  The four-electrode resistivity technique in anisotropic media: theoretical analysis and application on myocardial tissue in vivo , 1993, IEEE Transactions on Biomedical Engineering.

[27]  Stuchly,et al.  DIELECTRIC PROPERTIES OF BIOLOGICAL SUBSTANCES–TABULATED , 1980 .