A three-dimensional observation of acid phosphatase-positive structures in rat testis by high voltage electron microscopy.

Using a fixative of low concentrated glutaraldehyde in PIPES, we examined three-dimensional structures of acid phosphatase (ACPase) activity in the cells of testes of normal adult and 30 min heat-treated rats by high voltage electron microscopy. There were less ACPase-positive structures in germ cells, but more in Sertoli cells, particularly in residual bodies, and also in macrophages lying between seminiferous tubules. Reaction products of ACPase were distributed in the trans-most cisternae of Golgi apparatus, many spherical lysosomes, and acrosomes. The elongated thread-like lysosomes (nematolysosomes) were absent on the testicular cells. After heat-treatment of rat testis, though ACPase-positive lysosomes increased in number, nematolysosomes were never seen in Sertoli cells and most of the other testicular cells; a number of rod-like lysosomes, however, emerged in macrophages. The results indicate that (1) Sertoli cells usually have more ACPase-positive lysosomal contents than germ cells; (2) Sertoli cells are less affected by stress which may largely hurt germ cells; (3) nematolysosome is not a ubiquitous structure in all the types of cells; and (4) the function of nematolysosomes in macrophages may involve in the disposition of disintegrated cells in rat testis.