ADENYLATE-CYCLASE IN MOUSE TESTIS

Adenylate cyclase has been localized cytochemically in mouse spermatids by means of a specific substrate, tetrasodium adenylylimidodiphosphate (AMP-PNP). With ATP as substrate, a heavy deposit was obtained, while AMP-PNP yielded a fine, circumscribed deposit. The reaction product always appeared to be membrane-bound and was present both in the early and the maturing spermatids, as well as in Sertoli cells. Spermatozoa which had been liberated into the lumen of the seminiferous tubules were cytochemically negative under the conditions of the present procedures. The specificity of the reaction was confirmed by using a specific inhibitor, alloxan, or by incubating the specimens in a complete medium without the substrate.