Plasma Membrane ATPase as a Key Site of Alteration by a Freeze-thaw Stress: Role in Recovery and Progressive Injury

Abstract

One of the first visual manifestations of freezing injury is the water soaked appearance of the tissue due to infiltration of the intercellular spaces with water (Levitt, 1980; Palta et al., 1977a). This is often accompanied by loss of turgor, and leakage of ions and organic solutes from the cell (Palta et al., 1977b; Palta et al., 1977c). Until recently it was believed that this leakage was due to a complete breakdown in membrane semipermeability and membrane rupture. Recent work of Palta and co-workers (Palta et al., 1982; Palta and Li, 1980) have established that ion leakage is due to a selective change in membrane transport properties and that freezing injury was either reversible or irreversible depending upon the initial extent of injury. From these studies they proposed that freezing stress results in alteration of the functions of plasma membrane ATPase in the early stages of injury (Palta and Li, 1980). Results supporting this hypothesis have been reported by studying changes in plasma membrane (PM) ATPase after freezing injury and cold acclimation (Helleregren et al., 1985; Ishikawa and Yoshida, 1985; Jian et al., 1982).