Effects of Osteocalcin on Synthesis of Testosterone and INSL3 during Adult Leydig Cell Differentiation

Figure 10

Electron microscopic view of testicular tissue samples of EDS-administered subjects (Group 2). (a) Membrane propria (MP), Sertoli cells (S), spermatocytes (Spt), and spermatids (Spd) were in normal structure in control subjects of Group 2 (Group 2A). Tight connections between the Sertoli cells (arrowhead) were seen in normal structure. Tubular-type mitochondria (M) and abundant lipid droplets (L) were observed in the cytoplasm of Leydig cells (LC). N: nucleus; bar = 2 μm. (b) An increase in membrane propria (MP) total thickness and giant vacuoles (V) between Sertoli cells (S) and spermatocytes (Spt) was observed in GnRH-antagonist-administered subjects of Group 2 (Group 2B). Ls: lysosome; bar = 2 μm. (c) Low electron density and agranular endoplasmic reticulum (SER) vacuolization were seen in some Leydig cells (LC) in testicular tissue samples of Group 2B. Mitochondria (M) were intact. Bar = 0.5 μm. (d) In some Leydig cells, a decrease in the cytoplasmic volume and an increase in peripheral heterochromatin patches in the nucleus (N) were also observed in testicular tissue samples of Group 2B. Bar = 0.5 μm. (e) Thickening and irregularity in the membrane propria (MP) were seen to continue. A relative decrease in the volume of the vacuoles between Sertoli cells (S) and spermatocytes (Spt) was observed in GnRH-antagonist-and-osteocalcin-administered subjects of Group 2 (Group 2C). Bar = 2 μm. (f) A decrease in the cytoplasmic volumes of Leydig cells (LC) and a decrease in the amount of indentation in the nucleus (N) and in the content of heterochromatin were observed in testicular tissue samples of Group 2C. Bar = 0.5 μm. (g) Sertoli cells (S), spermatogonia (Spg), and spermatocytes (Spt) surrounded by membrane propria (MP) were seen to be normal in only-osteocalcin-administered subjects of Group 2 (Group 2D). Bar = 1 μm. (h) Numerous lipid droplets (L) were observed in the cytoplasm of Leydig cells (LC) containing the nucleus (N) in normal structure in testicular tissue samples of Group 2D. F: fibroblast; bar = 0.5 µm.