Dutt M K
Microsc Acta. 1982 Jul;86(2):147-56.
This paper reports on the use of some Schiff-type dye-reagents prepared with oxalic acid and sodium thiosulphate. Some of the dyes, such as azure A, azure B, toluidine blue O, thionine, brilliant cresyl blue, and methylene violet were also prepared with oxalic acid and sodium thiosulphate but fortified with disodium hydrogen phosphate. It has been found that all these dye-reagents, barring neutral red-SO2, when used on acid-hydrolysed mammalian tissue sections under UV rays yield far better staining of the DNA-aldehyde molecules than is possible in controls stained under normal laboratory conditions. Sections stained with any of the dye-reagents under UV rays do withstand treatment in SO2 water or acid water without showing any leaching of the dye from the nuclei. Aqueous solutions of all these dyes can also be used to stain DNA-aldehyde molecules of acid-hydrolysed tissue sections. But sections stained with aqueous solutions of the azures, safranine, phenosafranine, and methylene violet when treated with SO2 water reveal considerable leaching of the dye from the nuclei. However, leaching does not occur when these dyes are used as SO2-containing dye-reagents under UV rays. It has, therefore, been concluded that in the case of staining with the azures, safranine, phenosafranine, and methylene violet, containing SO2, the reaction under UV rays is of Feulgen-type. In the case of staining with toluidine blue-SO2, thionine-SO2, and brilliant cresyl blue-SO2 under UV rays, the mechanism of staining is also of Feulgen-type but it is due to liberation of the dye molecules from their more or less colourless states that react with the DNA-aldehyde molecules producing nuclear colouration as though these dyes are in aqueous solution. This interpretation is based on the fact that sections from which RNA has been extracted selectively with cold concentrated phosphoric acid when treated with these dye-reagents under UV rays also stain DNA-phosphate groups. The increased staining intensity of the nuclei produced with the majority of the dye-reagents under UV rays as compared with control sections stained under usual laboratory conditions has been considered to be due to electronic excitation of the dye molecules thus facilitating binding between more molecules of DNA-aldehyde and of dye. Possible significance of these findings has been discussed.
本文报道了用草酸和硫代硫酸钠制备的一些席夫型染料试剂的应用。一些染料，如天青A、天青B、甲苯胺蓝O、硫堇、灿烂甲酚蓝和亚甲紫，也用草酸和硫代硫酸钠制备，但添加了磷酸氢二钠。已经发现，除中性红 - SO₂外，所有这些染料试剂在紫外线照射下用于酸水解的哺乳动物组织切片时，对DNA - 醛分子的染色效果比在正常实验室条件下染色的对照要好得多。用任何一种染料试剂在紫外线照射下染色的切片在SO₂水或酸性水中处理时，不会出现染料从细胞核中渗出的情况。所有这些染料的水溶液也可用于染色酸水解组织切片的DNA - 醛分子。但是，用天青、番红、酚番红和亚甲紫的水溶液染色的切片在用SO₂水处理时，会出现染料从细胞核中大量渗出的情况。然而，当这些染料在紫外线照射下用作含SO₂的染料试剂时，不会发生渗出。因此，可以得出结论，在用含SO₂的天青、番红、酚番红和亚甲紫染色时，紫外线照射下的反应是福尔根型的。在用紫外线照射下用甲苯胺蓝 - SO₂、硫堇 - SO₂和灿烂甲酚蓝 - SO₂染色时，染色机制也是福尔根型的，但这是由于染料分子从或多或少无色状态释放出来，与DNA - 醛分子反应产生细胞核着色，就好像这些染料处于水溶液中一样。这种解释基于这样一个事实，即当用冷浓磷酸选择性提取RNA后的切片在紫外线照射下用这些染料试剂处理时，也会对DNA - 磷酸基团进行染色。与在通常实验室条件下染色的对照切片相比，大多数染料试剂在紫外线照射下使细胞核染色强度增加，被认为是由于染料分子的电子激发，从而促进了更多DNA - 醛分子与染料分子之间的结合。已讨论了这些发现的可能意义。
