A role for glial fibrillary acidic protein (GFAP)-expressing cells in the regulation of gonadotropin-releasing hormone (GnRH) but not arcuate kisspeptin neuron output in male mice.
GnRH neurons are the final central neural output regulating fertility. Kisspeptin neurons in the hypothalamic arcuate nucleus (KNDy neurons) are considered the main regulator of GnRH output. GnRH and KNDy neurons are surrounded by astrocytes, which can modulate neuronal activity and communicate over distances. Prostaglandin E2 (PGE2), synthesized primarily by astrocytes, increases GnRH neuron activity and downstream pituitary release of luteinizing hormone (LH). We hypothesized that glial fibrillary acidic protein (GFAP)-expressing astrocytes play a role in regulating GnRH and/or KNDy neuron activity and LH release. We used adeno-associated viruses to target designer receptors exclusively activated by designer drugs (DREADDs) to GFAP-expressing cells to activate Gq- or Gi-mediated signaling. Activating Gq signaling in the preoptic area, near GnRH neurons, but not in the arcuate, increases LH release in vivo and GnRH firing in vitro via a mechanism in part dependent upon PGE2. These data suggest that astrocytes can activate GnRH/LH release in a manner independent of KNDy neurons.
['Vanacker|Charlotte|C|0000-0001-5289-9298', 'Defazio|R Anthony|RA|0000-0001-7302-7528', 'Sykes|Charlene M|CM|', 'Moenter|Suzanne M|SM|0000-0001-9812-0497']
D000818:Animals D001111:Arcuate Nucleus of Hypothalamus D005904:Glial Fibrillary Acidic Protein D007987:Gonadotropin-Releasing Hormone D059648:Kisspeptins D007986:Luteinizing Hormone D008297:Male D051379:Mice D008822:Mice, Transgenic D009474:Neurons D010902:Pituitary Gland D011301:Preoptic Area
GnRH kisspeptin LH hypothalamus mouse neuroendocrinology neuroscience reproductive biology