부산대학교 도서관

Maillet's OsO4-ZnI2 fixation staining can be combined with a subsequent counterstaining by Alcian blue or aldehyde fuchsin to demonstrate neurosecretory cells in addition to cytological details of the nerve tissue. This technic has been applied to various annelids: Eisenia foetida (Oligochaeta), Erpobdella octoculata (Achaeta) and Nereis diversicolor (Polychaeta). The material is fixed in a 1:4 mixture of 2% OsO4 and 3% ZnI2 for 15 nr, embedded in paraffin, sectioned at 5 μ and the sections alternatively mounted on two glass slides. One of these is oxidized by a solution of 0.3% KMnO4 acidified by 0.6% H2SO4 and counterstained with 1% Alcian blue, pH 0.2, the other one is mounted in balsam. The two preparations may then be compared to locate the neurosecretory cells among the other neurons shown on a slide treated only by the OsO4-ZnI2. Secretory cells are not stained by Maillet's reagent; except for their Golgi bodies and their cellular and nuclear membranes. The zone of grains which is generally strongly stained by the Alcian blue takes a yellowish hue from the OsO4-ZnI2 fixation. This method could be successfully applied to the histological controls in regeneration experiments. In these last ones, we must simultaneously observe the regeneration of the nervous fibres and the possibility of intervention of neurosecretory elements.