Kanasaki H, Oride A, Mijiddorj T, Sukhbaatar U, Kyo S. How is GnRH regulated in GnRH-producing neurons? Studies using GT1-7 cells as a GnRH-producing cell model. Gen Comp Endocrinol. https://www.sciencedirect.com/science/article/pii/S0016648017300680
Highlights
Although GnRH neurons certainly play a pivotal role in the HPG axis, the detailed mechanisms of their functional network, including regulatory systems, remain unknown. After the discovery of the indispensable role of kisspeptin in the development of human reproductive functions, our understanding of the neuroendocrine regulation of the HPG axis was revolutionized, and it is now recognized that kisspeptin acts upstream of GnRH and is responsible for sex steroid feedback mechanisms.
Kisspeptin can stimulate gonadotropin release from the pituitary gland by stimulating GnRH release and GnRH antagonists prevent kisspeptin-induced gonadotropin release. Furthermore, it has been shown that GnRH neurons express kisspeptin receptors.
Nevertheless, the detailed mechanisms underlying the regulation of homogeneous populations of GnRH neurons are still largely unknown because of the limitations of experimental models used for investigation.
The hypothalamus consists of a complex network of distinct neuronal cells, and it is difficult to isolate single-cell populations of GnRH neurons. The establishment of GnRH-expressing cell lines has allowed us to examine the events happening at the single-cell level. In this review, we describe in vitro studies using a GnRH-producing cell model, GT1-7 cells, which have been used to examine how GnRH-producing cells respond to hypothalamic factors and how they are involved in GnRH synthesis.
Highlights
- The establishment of GnRH-expressing cell lines has allowed us to examine the events happening at the single-cell level.
- GT1-7 cells have proven to be a valuable GnRH-producing cell model for studying GnRH neurons.
- We describe how GnRH-producing cells respond to hypothalamic factors and how they are involved in GnRH synthesis.
Although GnRH neurons certainly play a pivotal role in the HPG axis, the detailed mechanisms of their functional network, including regulatory systems, remain unknown. After the discovery of the indispensable role of kisspeptin in the development of human reproductive functions, our understanding of the neuroendocrine regulation of the HPG axis was revolutionized, and it is now recognized that kisspeptin acts upstream of GnRH and is responsible for sex steroid feedback mechanisms.
Kisspeptin can stimulate gonadotropin release from the pituitary gland by stimulating GnRH release and GnRH antagonists prevent kisspeptin-induced gonadotropin release. Furthermore, it has been shown that GnRH neurons express kisspeptin receptors.
Nevertheless, the detailed mechanisms underlying the regulation of homogeneous populations of GnRH neurons are still largely unknown because of the limitations of experimental models used for investigation.
The hypothalamus consists of a complex network of distinct neuronal cells, and it is difficult to isolate single-cell populations of GnRH neurons. The establishment of GnRH-expressing cell lines has allowed us to examine the events happening at the single-cell level. In this review, we describe in vitro studies using a GnRH-producing cell model, GT1-7 cells, which have been used to examine how GnRH-producing cells respond to hypothalamic factors and how they are involved in GnRH synthesis.
