METAL SALTS-HEMATOXYLIN STAINING OF SKIN KERATOHYALIN GRANULES:

The stratum granulosum of the mammalian skin contains keratohyalin granules which have been shown to have an affinity for salts of aluminum, chromium, copper and iron. To determine whether these granules have an affinity for other elements and whether the granule-metal complexes can be stained, salts of 64 metals were tested. Histologic sections of animal and human skin were treated with 0.01 M solution of various metal salts for 4 hr, washed in distilled water and stained with 1:10,000 dilution of unoxidized hematoxylin in 0.01 M phosphate butffer, pH 7.0, for 4 hr. In the cationic state, Al, Cr, Ga, Hf, In, Fe and Zr formed dark blue granules. Be, Dy, Ho, Ir, Pb, Mn, Mo, Nd, Ni, Pt, Rh, Tb, U, Yb and Zn produced lighter blue granules. The granules produced by Bi were purple; Ta, brown-red; Nb and Ti, brown; Cu, greenish blue; Sn and Th, purplish red; Os, blue- or green-brown. The metals were not extracted by washing in water up to 72 hr. Some metals were extracted by 1 N HCl and by 10% Versene.