Abstract:
In a previous study on the effects of gestational and lactational exposure of para-nonylphenol
on male rats, we noted in both induced and uninduced rats, that variations in cleaved caspase-
3 immunostaining patterns were associated with distinct nuclear alterations in mainly basally
located germ cells (spermatogonia and preleptotene spermatocytes). These were re-analysed
and compared with cleaved caspase-3-labeled germ cells in the aging human and the
spermatogenically active catfish testis. In the rat testes, cytoplasmic immunostaining was
progressively associated with lateral compression of the nucleus, its break up into large pieces
which can contain immunostained marginated chromatin masses. The pale remnants of the
nucleus continued to shrink in size concomitant with the appearance of blue-purplish stained
regions in the cytoplasm similar in color to the condensed chromatin in spermatids, a
condition which was TUNEL-negative. These large clumps of chromatin also eventually
disappeared, giving rise to cells resembling cytoplasmic ghosts, a condition which was
TUNEL-positive. By contrast, the immunolabeled nuclei of human and catfish germ cells
condensed into a single mass, after which they lost immunoreactivity. To exclude the
possibility that these observations could reflect alterations in Sertoli nuclei, rat testicular
sections were probed with a mouse anti-human GATA-4 monoclonal (MHM) antibody. The
MHM was, however, the second of two GATA-4 antibodies tested, with a goat anti-mouse
polyclonal (GMP) initially used to label rat the Sertoli nuclei. GMP unexpectedly, but
distinctly labeled the complete development of the acrosome in the rat testis, a fortuitous
finding with utility for staging of the seminiferous epithelium.
