Bratislava Medical Journal Vol.116, No.5, p.321-325, 2015

o evaluate the effects of zinc oxide nanoparticles (ZNPs) on morphometric and stereological parameters of mouse testis.
Background: ZNPs are increasingly used in sunscreens, biosensors, food additives, pigments, rubber manufacture, and electronic materials. However, the potential toxicity of these nanoparticles is not well understood.
Methods: Experimental Groups (ZNP-1, ZNP-2 and ZNP-3) received one of the following treatments daily for 35 days: 5, 50 and 300 mg/kg ZNPs respectively. Right testis from each animal was fixed in bouin’s solution for measurement of total volume of testis, total volume of seminiferous tubules, total volume of interstitial tissue and total number of Leydig cells by stereological methods. Seminiferous tubule diameter and seminiferous epithelium height were assessed by morphometrical method. The left testicles were homogenized for measurement of testosterone concentration.
Results: There was a significant decrease in the weight of testicles in ZNP-3 groups.

The stereological and morphometrical parameters were significantly changed in ZNP-2 and ZNP-3 groups. ZNP-2 and ZNP-3 groups also showed a significant decrease in testosterone concentrations (p < 0.05).

Conclusion: This study demonstrated that ZNPs can change stereological and morphometrical parameters of the seminiferous tubules and reduce the number of Leydig cells (Tab. 3, Fig. 3, Ref. 36).