Fig. 1. Photomicrographs of rat testes stained with H&E (×400). (a) Control group showing normal seminiferous tubules with nearly normal spermatogenesis (St) and interstitial Leydig cells (arrow). (b) Zinc oxide nanoparticles group showing increased size of seminiferous tubules with normal spermatogenesis (St). (c) Doxorubicin group showing that most of seminiferous tubule with less spermatogenesis (St), while the interstitial capillaries appeared severely congested (Co). (d) Doxorubicin + zinc oxide nanoparticles group showing numerous intratubular vacuolations (arrows) with some normal spermatogenesis in seminiferous tubules (St).