Membrane permeability transition and dysfunction of rice mitochondria effected by Er(III)

Herein, the biological effects of heavy rare earth ion Er(III) on rice mitochondria were comprehensively investigated mainly by spectroscopic methods. The experimental results demonstrated that Er(III) could lead to the swelling of rice mitochondria, collapse of mitochondrial transmembrane potential, decrease of membrane fluidity, promotion of H(+) permeability and suppression of K(+) permeability. These further indicated that Er(III) could induce the mitochondrial permeability transition (MPT) and the dysfunction of rice mitochondria. The ultra-structure change of mitochondria observed by transmission electron microscopy (TEM) also proved that Er(III) induced MPT. Moreover, the testing results of the protective effect of four different agents on mitochondrial swelling implied that the thiol chelation on the mitochondrial inner membrane was the main reason that caused the MPT.