Suzuki H, Fukuyama K, Epstein J H, Epstein W L
J Invest Dermatol. 1978 Nov;71(5):334-9. doi: 10.1111/1523-1747.ep12529836.
Ultrastructural changes in nuclei synthesizing DNA were studied by cytochemical technique. Guninea pigs ears were UVB irradiated and TdR-H3 was injected intradermally into the irradiated sites 1 hr before biopsy. Areas of the epidermis containing more than 80% of cells in DNA (repair or premitotic) synthesis identified by light microscopic autoradiography were selected and cut at 600 A. The glycolmethacrylate sections were stained with uranyl acetate and lead citrate, and consecutive sections were incubated with 0.01% pronase and 0.5% RNase before staining in order to observe DNA. In cells undergoing DNA repair, the zone of DNA became discontinuous and DNA was scattered throughout the entire karyoplasm as small aggregates and fine filaments. Nuclei in S-phase showed essentially the same change, but quantitatively the disappearance of DNA from the nuclear membrane and distribution in the karyoplasm became much greater. These changes were not seen in specimens treated without cytochemical technique.
采用细胞化学技术研究了合成DNA的细胞核的超微结构变化。用紫外线B照射豚鼠耳朵，并在活检前1小时将氚标记胸腺嘧啶核苷（TdR-H3）皮内注射到照射部位。通过光学显微镜放射自显影确定表皮中DNA（修复或有丝分裂前期）合成细胞比例超过80%的区域，将其切成600埃厚的切片。将甲基丙烯酸乙二醇酯切片用醋酸铀和柠檬酸铅染色，连续切片在染色前用0.01%链霉蛋白酶和0.5%核糖核酸酶孵育，以便观察DNA。在进行DNA修复的细胞中，DNA区域变得不连续，DNA以小聚集体和细丝的形式散布在整个核质中。处于S期的细胞核显示出基本相同的变化，但从数量上看，核膜上DNA的消失以及在核质中的分布变得更加明显。在未采用细胞化学技术处理的标本中未观察到这些变化。
