Fusion of mitochondrial inner membranes by electric fields produces inside-out vesicles. Visualization by freeze-fracture electron microscopy.

The fusion of vesicular-shaped mitochondrial inner membranes was observed by a new approach which combines freeze-fracture electron microscopy and electric field-induced fusion. Results show that membrane events caused by the exposure to the electric field can be time-coordinated with sample freezing for subsequent analysis by freeze-fracture electron microscopy.