Research Areas of Interest
My research examines the effects of the maternal/fetal interaction on neural
development, specifically the effects of maternal progesterone on the development
of sex differences in the brain and behavior. One way in which steroid hormones
act in neurons is through interactions with nuclear steroid receptors. Therefore,
in order to examine when the developing brain first becomes sensitive to progesterone,
we have used immunocytochemistry to detect the expression of progesterone
receptors in both the fetal and neonatal brain.
Recent work in my lab has revealed that certain areas of the fetal rat
brain express progesterone receptor well before birth. The expression of
progestin receptor (PR-ir) in the medial preoptic nucleus (MPN) of rats
on the day of birth is high in males but virtually absent in females. The
MPN of rats is sexually dimorphic and mediates several sexually differentiated
behaviors in adulthood. These results suggest that the brain of the male
fetus may be more sensitive to maternal hormones than that of females and
that progesterone may play a critical and previously overlooked role in
the sexual differentiation of the brain.
With this work we have revealed that a novel role of the mother in the
development of the fetal CNS must be considered. We are currently examining
what hormonal signals trigger the differential expression of progesterone
receptor in male and female fetal brains and over what periods of development
this sex difference exists. In addition, we are very interested in pursuing
what role progesterone and its receptor play in mechanisms such as neuronal
differentiation, cell migration, cell death and other cellular events known
to contribute to sex differences in the CNS. This research can then be extended
to examine the role of maternal hormones in the development of sexually
differentiated behaviors such as sexual behavior and maternal behavior. |
Role
of Maternal Progestins in Cortical and Cognitive
Development