[Role of iron ions on tannin-iron method histochemical specificity (author's transl)]

In this work is studied the tannin-iron method specificity when the ferrous chloride is replaced by other iron compounds. Nervous tissue and rat duodenum cuts are used. Cuts were treated with tannic acid and after with FeCl3; FeCl2; FeOHCl2; FeAc2; Fe2O3; FeSO4; NH4Fe(SO4)2 or colloidal iron solution. Dilution effect from every one of aforementioned iron compounds too is studied. The obtained results with those furnished by the OTA method by using the tannic acid in identical conditions are compared. Also several treatments of blockade were carried-out. The obtained results prove that iron ions play a different role in the mucins staining than in other demonstrable substances coloration in the nervous tissue. In the same way evidences that the iron ion that joins the mucins in the tannin-iron method is the FeOH++ ion were obtained.