Morphological Changes of Mammalian Nucleoli during Spermatogenesis and Their Possible Role in the Chromatoid Body Assembling

Figure 1

Cytological and cytochemical analysis of the germ epithelium of Oryctolagus cuniculus. (a) Hematoxylin-eosin (HE); (c–e) toluidine blue (TB); (b, f–h) modified critical electrolyte concentration method (CEC); (i–k) Feulgen reaction; (l–n) silver ion impregnation. (a and b) General view of the seminiferous tubules, where we can observe the distribution of the somatic and germ cells through the seminiferous epithelium: s (Sertoli cell); go (spermatogonia); spI (primary spermatocyte); es (round spermatids); stz (elongated spermatids); *(residual bodies). (c, f, i, and l) spermatogonia with fully organized nucleoli. (d, g, j, and m) spermatocytes I exhibiting fragmented nucleolar material disperse through the nuclei. (e, h, k, and n Reassembly of the nucleolar structure could be observed in the nuclei of round spermatids. Reorganized nucleoli were not observed using the CEC method (h). (f, k, l, and n) arrows (nucleolar corpuscles). Bars: (a and b) 50 μm; (c–n) 20 μm.