Slices of normal rat liver and residual liver after a subtotal hepatectomy have been incubated in vitro. The intracellular concentrations of sodium and potassium that the tissue can maintain under these conditions has been determined for various intervals after subtotal hepatectomy, and the potassium flux per unit membrane area has been calculated. It was found that regenerating liver can maintain a potassium concentration of 152 mEq. per liter of intracellular water while the concentration in normal liver under the same conditions was 93.7 mEq. per liter. The sodium concentration of regenerating liver was 81.7 mEq. per liter of intracellular water compared to 143 mEq. per liter in normal liver. The potassium flux per unit membrane area of both tissues was identical at 35 ° C. In addition, the ability of normal liver to accumulate potassium and extrude sodium is more sensitive to a temperature decrease than is that of 48 hour regenerating liver. The most likely explanation for this phenomenon is a decrease in membrane permeability to sodium and potassium during growth. These changes are seen at 12 hours after a subtotal hepatectomy and reach a maximum from 48 hours to 5 days. It is postulated that this change in permeability is a possible mechanism for initiating mitosis.
|Original language||English (US)|
|Number of pages||9|
|State||Published - Aug 1 1966|