Background: Studies show that antioxidants are beneficial for male infertility. Considering that sesame seed contains several important antioxidants, this study was designed to examine the effect of a sesame seed regimen on the testicular structure and sex hormones in adult rats.

Materials and Methods: This experimental study was conducted on 30 adult male Wistar rats (200 g) prepared from Physiology Research Center at Kashan University of Medical Sciences. Rats were randomly divided into the experimental and control groups. The control group received the standard regimen, while the experimental group received a special regimen (70% standard food+30% sesame seed) after weaning for 12 weeks. At the end of the study, the weight and volume of the testis and seminiferous tubules, the lumen epithelium diameter, LH, FSH and testosterone levels were evaluated.

Results: No significant difference was found between the two groups in body weight, the weight and volume of the testis and the volume percentage of vessels in seminiferous tubules, while the mean number and motility of sperms in epididymis, the number and volume percentage of epithelial cells, lumen and interstitial space as well as the diameters of the tubules were significantly different in the experimental compared to the control group (P<0.0001). Moreover, there was a significant difference between the two groups in LH level (P=0.03).

Conclusion: Sesame seed intake improves the testicular parameters, fertility and sperm production in male rats.