Abstract:
This study investigated the effects of tamoxifen, an
oestrogen receptor antagonist on fertility of male rats. This was done by
applying the drug directly to the epididymis through implantation of silastic
rods containing 50% of drug (day 0) and subjecting these rats to serial mating
on day 3, and then approximately at weekly intervals upto day 70. The
tamoxifen treatment caused significant impairment in sperm numbers in the
ejaculate possibly via spermatogenic arrest (between days 21-42), fertility
index (on days 28 and 35), number of uterine implants (on day 35) orquantal
pregnancy (on day 35) and a significant elevation in pre-implantation loss
(on day 35). On the other hand, tamoxifen treatment had no significant
effects on libido and in post-implantation loss. It is concluded that tamoxifen
mediated its antifertility action mainly through production of oligozoospermic
ejaculates possibly via the inhibition of Sertoli cell function.
