Deformities in the head region of late spermatids of hypophysectomized-hormone-treated rats.

Testosterone capsules implanted in hypophysectomized rats prevented tubulobulbar complexes from forming in many late spermatids. These spermatids also displayed an accumulation of cytoplasm (swelling) in the perinuclear region of the head. Other spermatids with normal or near-normal numbers of tubulobulbar complexes showed a typical perinuclear space. The results indicate, but do not prove, that development of tubulobulbar complexes (and their subsequent phagocytosis) is essential for the normal elimination of cytoplasm that takes place prior to sperm release.