Location of Zn in the testicle of the rat.

We studied the location of Zn in the testicle of the Wistar rat using the Timm histochemical technique, autoradiography with 65Zn and the dynamic pathway of 65Zn in the organ. Locations of Zn in several cellular components of the spermatogenic chain and in the Leydig cells were observed. This location was proved statistically by a quantitative analysis of the autoradiographs. The presence of Zn in the testicle, prostate and the adrenal gland could be related to the activation of the enzyme beta-hydroxy-steroid dehydrogenase although this fact does not exclude any other function of this metal, as far as we know.