g) of the. Charles. River strain were used. They were housed in a light-controlled ...... Glover,. J. S.. (1963). The preparation of I's' labeled human growth hormone of high .... C. (1974). Effect of testosterone on serum prolactin in the castrated rat.
BIOLOGY
OF
REPRODUCTION
Effects
25, 6-14
(1981)
of Testosterone, Impaired
Dihydrotestosterone,
Prolactin
Response
A.
ZYLBER-HARAN,’
HENIA
Department
Rat
GERSHMAN
of Endocrinology Shaare
Zedek
and
and
Medical
Jerusalem
91000,
on the
to Metoclopramide
in the Castrated EDIT
and Estradiol
IRVING
M.
SPITZ
Metabolism,
Center, Israel
ABSTRACT was designed to assess the effect of three testicular steroids, testosterone, dihydrotestosterone, and estradiol, on PRL secretion in castrated rats. This has been done by evaluating the effect of androgens and estrogens and their antagonists, alone or in combination, on metoclopramide (MET)-induced PRL secretion in the castrated male rat. Ventral prostate and seminal vesicles retained normal weight after treatment of castrated rats with testosterone propionate (TP) and dihydrotestosterone (DHT). This effect was partially antagonized by the antiandrogen cyproterone acetate (CA) which in itself had no effect. TP, as well as DHT and EB, prevented the rise of plasma and pituitary LH and plasma FSH consequent to castration. CA partially blunted the TP and completely blocked the DHT effect, indicating that it acts as an antiandrogen. Nafoxidine hydrochloride (NH) antagonized the effect of EB, but not of TP on gonadotropins. This indicates that in combination with EB, NH acts as an antiestrogen. The PRL response to MET was significantly reduced in castrated rats (P
