Zeranol induces deleterious effects on the testes and the prostate gland of mature rats

Endocrine disrupters have been shown to affect the male and female reproductive systems and to alter potential fertility.

This study was conducted to evaluate the effect of a continuous-release pellet containing 12 mg of zeranol for 30 days on the testes and the prostate gland of mature male rats.

Zeranol treatment induced significant decrease of the testes and the prostate gland weights which were associated with a remarkable atrophy of the testicular seminiferous tubules and prominent regression of the glandular compartment of the prostate gland. However, zeranol treatment increased the thickness of the periductal layer of stromal cells of the prostate gland from a thin layer that express intense immunostaining of SM-actin and mild vimentin to a thicker layer of cells that exhibited intense immunostaining for both SM-actin and vimentin.

These findings suggest that zeranol-induced changes to the prostate gland could result from either a direct effect of zeranol on the prostate gland or an indirect effect by interfering with testosterone production through disruption of testicular function.