The microglia in brain granulomatoses. Histo-enzymological study.

The microglial participation in the different granulomatous processes was studied by silver impregnation techniques and histoenzymological methods. In florid granulomatous areas two types of metallophilic cells were detected, corresponding to the common macrophages and perhaps to the ameboid modification of the microglia. Hydrolytic enzyme preparations showed a pattern of distribution and intensity similar to that of the impregnated cells. Only in the adjacent nervous parenchyma the different methods evidenced the presence of hyperplastic ramified microglia associated with reactive astrocytes.