Ultrastructural studies on rat skin autografts

The epidermis of rat skin autografts was studied during the first 14 days of the healing period using light and electron microscopy. Patches of necrotic cells were found on the second and third days while the major part of the cells only showed minor changes from normal skin. At the ultrastructural level the last mentioned cells showed changes, comprising wrinkling of nuclear envelope, aggregation of chromatin, irregular and swollen mitochondria, appearance of different types of vacuoles and a reduction in size and number of keratohyalin granules. These changes were most pronounced on the third day after transplantation. After 8 days only minor changes from the normal epidermis were found and after 14 days the epidermis of skin autografts exhibited a complete healing and regeneration.