4 research outputs found
Influence of a single treatment with vitamin E or K (hormonal imprinting) of neonatal rats on the sexual behavior of adults
The
effect
of
a
single
neonatal
treatment
(imprinting)
with
vitamin
E
or
vitamin
K
1
on
the
sexual
activity
of
three-month
old
rats,
was
studied.
In
female
animals
vitamin
E
treatment
significantly
lowered
the
Meyerson
index
and
lordosis
quotient,
among
males
there
were
significantly
more
inactive
animals
and
no
multiple
ejaculations
could
be
observed.
Vitamin
K
1
treatment
caused
only
slight
changes
in
the
same
direction,
in
both
sexes.
Considering
also
earlier
results
concerning
vitamin
A
and
D
neonatal
treatments
(alterations
in
receptor
binding
capacity,
sex
hormone
levels
and
sexual
behavior),
and
receptorial
changes
caused
by
neonatal
vitamin
E
and
K
1
treatments,
the
present
experiment
also
calls
attention
to
the
lifelong
effects
of
perinatal
treatment
with
lipid
soluble
vitamins
Effect of tamoxifen treatment at adolescent age on the sexual behaviour and steroid hormone receptor binding of adult female rats
Hormonal imprinting takes place perinatally, at the first encounter between the target hormone and its developing receptor. However, there is a secondary critical period of imprinting at puberty. In these periods molecules similar to the hormones (members of the same hormone family, antagonists, certain environmental pollutants, etc.) can cause faulty imprinting with lifelong consequences. In the present experiments 5+2 days of tamoxifen treatment (120mg/day) at adolescent age dramatically (from approx. 40% to 10%) reduced the sexual activity (Meyerson index and lordosis quotient) of female rats, soon after the finishment of the treatment and between four to six weeks after treatment. Similar results were observed in animals neonatally treated with allylestrenol and tamoxifen treated at puberty. Thymic glucocorticoid receptor and uterine estrogen receptor binding capacity were not influenced
Effect of single neonatal treatment with the soy bean phytosteroid, genistein on the sexual behavior of adult rats
Hormonal imprinting develops during the perinatal critical period, when the target hormone meets the yet unmatured receptor. As a consequence of imprinting the receptor accomplishes its maturation reaching the binding capacity characteristic to adults. In this period in the presence of foreign molecules similar to the target hormone faulty imprinting may occur with life-long consequences. Soy bean contains phytosteroids which can mimic estrogen effects. In the present experiments single genistein (20 μg) or combined genistein + benzpyrene (20 μg) treatments were done neonatally and the sexual behavior of male and female adult animals was studied. Genistein significantly increased the lordosis quotient of females, which was compensated by neonatal benzpyrene treatment. Genistein also enhanced the sexual activity of males, and this was significantly not reduced by parallel benzpyrene treatment. The results show that neonatal genistein exposure can imprint sexual activity for life and the presence of a second imprinter can modify genistein's behavioral effect