Accumulation of lanthanum by rat liver mitochondria.

The interaction of La(3+) with rat liver mitochondria was examined with a wide variety of techniques permitting measurement of respiratory and structural responses. It is concluded that La(3+) is accumulated by mitochondria in a process that is at least partially energy-dependent, and is bound with quite high affinity to membrane-associated sites both external and internal to the inner membrane. The relative insensitivity of the accumulation process to respiratory inhibitors and to the permeant anion acetate has interesting implications for the mechanism of active cation transport.