[Electron histochemical characteristics of laser necrosis]

Linear or dot-shaped lesions were inflicted on rat liver with Nd:YAG laser, and fine structural alterations of hepatocytes were studied in the specimens processed for an endoplasmic reticulum (ER) marker glucose-6-phosphatase (GP). 5-7 s after irradiation a severe cell damage and GP inhibition occurred near the lesions, with less injured cells located laterally. 24 hr later the zone of the necrosis increased markedly. An autolytic decomposition in the newly formed necrotic area was much more pronounced as compared to the area of the initial necrosis. Phagocytic resorption of the intensively irradiated tissue was retarded this explaining some clinical observations on the long-term healing after Nd:YAG laser surgery. Based on our observations the so-called contact regimen of the irradiation is recommended due to the small size of the initial necrosis produced with this method. The various patterns of cell injuries including some changes in ER and enzyme GP as its marker are described in detail.