Cellular potentials of normal and cancerous fibroblasts and hepatocytes

Several lines of investigation point to differences in electrical properties between normal and cancerous cells. Several tumor lines have low-resting membrane potentials. A few comparisons have been made between normal and tumor cells within the same tissue cell type. This study compares the cellular or transmembrane potential of hepatocytes and fibroblasts in both normal and tumor cells. High-impedance micropipets were used to record intracellularly in vivo in Buffalo rat hepatocytes and Morris 7777 hepatoma cells, as well as A/J mouse corneal fibroblasts and poorly differentiated fibrosarcoma cells. Rat hepatocytes had a mean membrane potential of -37.1 +/- 4.3 (S.D.) mV compared to -19.8 +/- 7.1 mV in the hepatoma cells. Mouse corneal fibroblasts measured -42.5 +/- 5.4 mV, while cells of mouse fibrosarcoma were -14.3 +/- 5.4 mV. The membrane potentials of the tumor cells were lower in both instances than in their normal counterpart (statistically significant at p = 0.001 for both tissue cell types). This supports the notion that lower cellular or membrane potentials may play a significant role in the altered physiology of the tumor cell.