Histology comparing WT and GCKO seminiferous tubules and epididymides at 5, 8 and 10 weeks.

<p>(A) In comparison to WT seminiferous tubules at 5 weeks, GCKO sections show tubules with increased lumen diameters and few elongating and elongated spermatids (*). By 8 weeks, cross sections from GCKO testes show prominent pynotic cells (arrows) and reduced numbers of elongating and elongated spermatids. By 10 weeks, cross sections of GCKO testes show further enlargement of tubule lumens and absence of elongating spermatids in the majority of tubules. (B) Epididymides of WT mice at 5 weeks and GCKO mice at 5, 8 and 10 weeks showing reduced sperm numbers in epididymides of knockout mice by 5 weeks and the absence of mature spermatozoa in GCKO epididymides at the 8 and 10 week timepoints.