Ultrastructural changes induced by hyperthermia in Chinese hamster V79 fibroblasts

The effects of hyperthermic treatment on some intracellular components and on the general morphology of Chinese hamster V79 fibroblasts have been studied. After 1 h of heating at 42 degrees C cells show small interruptions of the plasma membrane, dilation of the mitochondrial cristae and dissociation of the polyribosomes. These modifications become progressively more pronounced after 1 or 3 h treatment at 43 degrees C. Severe alterations in the general morphology of the cells are evident after 1 h heating at 45 degrees C.