The effect of microgravity on tissue structure and function of rat testis. Ye Ding, Jin Tang, Jun Zou, Ruiping She, Yinghua Wang, Zhuo Yue, Jijing Tian, Kangkang Xia, Jun Yin and Desheng Wang. Braz J Med Biol Res 2011; 44: 1243-1250.

Figure 1. Histopathological analysis of rat testes with HE staining by light microscopy. A, E, The normal structure of rat testes in the control group for 7 and 14 days, respectively. B, F, The morphology of rat testes of the tail traction group for 7 and 14 days, respectively. C, In the 7-day tail suspension group, the testicular tubules were arranged sparsely (arrow) with degeneration and necrosis of the spermatogenic cells (arrowhead). D, In the 7-day tail suspension group, the spermatogenic cells of the seminiferous tubules became loose, sparse and disorderly, with the formation of a syncytial structure (arrow). G, In the 14-day tail suspension group, protein fluid exudations (arrow) were conspicuously present in interstitial tissue and all germ cells had disappeared (arrowhead). H, In the 14-day tail suspension group, all germ cells had disappeared, with only a small number of residue and seminoma cells (arrow) being left; also, obvious fibroplasia was observed in interstitial tissue (arrowhead).