We have demonstrated that @entity251 -bovine serum albumin conjugate labeled with 2-nm colloidal gold ( @entity251 -BSA-gold) injected into the vascular system of @entity35 becomes visible as @entity575 deposits on the sections of tissues embedded in @entity990 resin after @entity575 enhancement and enters the @entity342 -target cell nuclei, e.g. round spermatids, but not the non-target cell nuclei. The diameter of the @entity575 deposits depends on the duration of @entity575 enhancement. In this study, to make clear the transfer route of @entity251 -BSA-gold into the round spermatid nucleus, the testis of @entity35 injected @entity251 -BSA-gold was observed under electron microscope after @entity575 enhancement for short periods of time. The small @entity575 deposits were present on the cell membrane, vesicles, Golgi region, acrosome, subacrosomal space, both the post-acrosomal and the subacrosomal nuclear envelope, and the nucleoplasm in the cap-phase spermatids. The @entity575 deposits were also found in the perinuclear cisterna of post-acrosomal nuclear envelope, but not in the nuclear pore. When the spermatids were observed at high-power magnification without the @entity575 enhancement, the outer nuclear membrane showed many irregular invaginations toward the inner nuclear membrane in the post-acrosomal nuclear envelope. Furthermore, a double-membrane-like vesicle seemed to be present in the nuclear envelope. In the vesicle, the gold particles were present along the inner membrane. These results suggest that @entity251 -BSA-gold can enter the nucleoplasm through some route provided by the nuclear double membranes in both the post-acrosomal and the subacrosomal nuclear envelope.

Nuclear translocation of gold labeled- @entity251 -bovine serum albumin conjugate through the nuclear double membranes in XXXX spermatids.

@entity251 :: ('MESH:D013739', 'Chemical') :: ['testosterone'] @entity575 :: ('MESH:D012834', 'Chemical') :: ['silver'] @entity990 :: ('CHEBI:30721', 'Chemical') :: ['epoxy'] @entity342 :: ('CHEBI:50113', 'Chemical') :: ['androgen'] @entity35 :: ('10116', 'Species') :: ['rat']
@entity35 :: (10116,Species) :: ['rat']
