Fig. 2.

CB₂ immunofluorescence staining of differentiating male germ cells. Immunofluorescence staining for CB₂ receptors (red signal), Hoechst nuclear counterstain (blue signal) and merged images of isolated testicular germ cells at different stages of differentiation. (A) Immunodetection of CB₂ receptors in: spermatogonia (Top), pachytene spermatocytes (Middle) and round (r-spt) and elongated (e-spt) spermatids (Bottom). Note that the immunofluorescence is also localized in vescicles containing only the cytoplasm that is released from the cell during spermiogenesis (residual bodies, rb); (B) High-magnification of CB₂ immunofluorescence pattern in dividing and interconnected spermatogonia.