Kinetics of the enzymatic pattern in the testis. I. Stage dependence of enzymatic activity and its relation to cellular interactions in the testis of the Wistar rat.

The "morphology" of the enzymatic activities of thiamine pyrophosphatase (TPPase), acid phosphatases (ACPases), adenosine triphosphatase (ATPase) and steroid-3 beta-ol dehydrogenase (St-3 beta-ol DH) has been described using as a basis the classification of the seminiferous epithelium of the rat into 14 stages as proposed by Leblond and Clermont (1952a, b). It was demonstrated (Figs. 1, 2) that 1. the kinetics of the enzymatic pattern is correlated with the developmental stages during spermatocyto- and spermiogenesis, and that therefore the chemocytostructure, especially of the germ cells, shows characteristic changes. 2. the enzymatic pattern yields information on the chemohistostructure of the testis, and thus indicates interactions between the germ cells and the coordinated somatic cells. This is valid especially for the behaviour of the "marker enzymes" TPPase and ACPases. Initially the activity of both enzymes is distributed in the cytoplasm: TPPase appears in stage VII in the preleptotene spermatocytes, and ACPases appear in stage VII in the pachytene spermatocytes. In the following stages the activity of TPPase and ACPases increases and becomes more and more concentrated, i.e. from stage IX to XIV and thereafter from stage I to XIII in the case of TPPase, and from stage I to XIII in the case of ACPases. Finally the enzymatic activity of both TPPase and ACPases is arranged in spherical bodies near the nucleus of the spermatocytes. Thus the late pachytene and diplotene spermatocytes, as well as the spermatocytes in diakinesis, are characterized by deeply stained spherical dots covering the region of the Golgi apparatus. Both enzymes disappear during the maturation divisions--parts of the cytoplasm of the II-spermatocytes during interphase react weakly positive--, reappear in the Golgi region of the newly formed spermatids in stage I, remain there up to stage V in the case of ACPases, and up to stage VII in the case of TPPase. From stages VIII to XIV TPPase is weakly positive in the Golgi apparatus of the elongating spermatids, moving within the cytoplasm from the head region towards the tail. Finally they appear in the cytoplasm of the Sertoli cells: (1) ACPases appear in the borderline region between the Sertoli cells and the elongated spermatids in stages XII to XIV (2) TPPase first appears in the basal region of the Sertoli cells in stages XI to XIV, and becomes positive in the subsequent stages I to IV as "streamer like" bands from the basement membrane up to the heads of the elongated spermatids. Both enzymes disappear gradually during stages I to III and IV to V respectively. Stage dependence of ATPase can be observed in the apical region of the Sertoli cells around the heads and the middle pieces of the elongated spermatids. ATPase appears for the first time in stages IX to X, and becomes increasingly more and more concentrated and condensed up to the point when the newly formed spermatozoa are released in stage VIII...