Mc. Oliveira et al., EFFECT OF ESTROGEN AND NEUROLEPTICS ON PROLACTIN SECRETION AND IMMUNOREACTIVE PROLACTIN CELLS, Brazilian journal of medical and biological research, 29(4), 1996, pp. 521-525
The use of estrogen and dopamine receptor antagonists is associated wi
th elevated prolactin levels and, in rats, chronic estrogen treatment
is also associated with lactotroph proliferation. In this study, halop
eridol, fluphenazine, sulpiride and metoclopramide, alone or combined
with estradiol, were administered to Wistar rats. Pituitary weight, se
rum prolactin levels and percent of immunoreactive prolactin cells in
the anterior pituitary glands were determined at the end of 60 days of
treatment. The pituitary weight of rats treated with estrogen alone o
r in combination with other drugs was significantly higher than the co
ntrol group. The serum prolactin level was higher than the upper confi
dence limit in all but three of the 90 treated rats. While in the cont
rol group the percent of immunoreactive prolactin cells was 20%, admin
istration of the neuroleptic drugs and metoclopramide increased this p
ercent to approximately 30%, and estrogen alone or in combination with
one of the neuroleptic drugs increased it to approximately 40%. The r
esults presented here demonstrate the relationship between prolactin s
ecretion and prolactin cell number when different neuroleptics and rel
ated drugs are used.