Abstract
Estrogen regulation of gonadotropin-releasing hormone (GnRH) neuronal activity plays
a crucial role in homeostatic regulation of the hypothalamic-pituitary-gonadal axis.
Estrogen also coordinates a complex series of physiological changes culminating with
a surge of gonadotropin secretion that triggers ovulation of a developed follicle
from the ovary. The coordinated functions of estrogen ensure that the female will
elaborate appropriate reproductive behaviors ultimately designed to deliver sperm
to the oocyte and to provide a receptive uterine environment for the fertilized embryo.
Although the effects of estrogen on GnRH neuronal function have long been proposed
to be indirect due to the presumed lack of estrogen receptors in GnRH neurons, the
identification of alternative estrogen signaling pathways, including estrogen receptor
(ER)β and membrane ERs such as GPR30, has put the focus back on estrogen’s effect
at the level of the GnRH neuron itself. One candidate to mediate the effects of estrogen
is the β isoform of the estrogen receptor. We review the evidence for a role for ERβ-mediated
regulation of GnRH neuronal function.
Keywords
GnRH - estrogen receptor-β - HPG axis
