Effect of estradiol benzoate on reproductive organs and fertility in the male rat.

The effects of estradiol benzoate (E2B) at a dose of 50 micrograms/day per rat for 7, 15 and 24 days on some androgenic parameters, viz. organ weights including those of pituitary, succinate dehydrogenase, acid phosphatase, fructose, cholesterol and protein of epididymis, vas deferens, accessory glands and fertility in male rats were investigated. The semen characteristics and standard electron microscopy (SEM) study on sperm morphology of cauda epididymis were also carried out. The results revealed that most of the androgenic parameters were decreased by E2B administration, whereas the accumulation of cholesterol and protein occurred in testis and epididymis due to androgen deprivation to target organs. This deprivation effect also led to a reduction in testicular and cauda epididymal sperm population, loss of motility in the latter and an increase in number of abnormal spermatozoa, thereby manifesting 100% failure in fertility in treated animals. Moreover, these effects were related to the duration of the treatment. Thus, the estradiol benzoate showed androgen antagonistic and antifertility effects in rats.