Our studies during the last years have caused a paradigm change by showing that the origin of estrogen-induced synaptic plasticity in the hippocampus is not the ovaries, but the hippocampus itself, thereby identifying estrogen as a neuromodulator independent of gender. Hippocampal neurons of rats of both genders are able to synthesise estrogens de novo from cholesterol. This hippocampal estrogen synthesis is essential for the preservation of spine synapses. The inhibition of estrogen synthesis in vivo as well as in vitro causes a loss of spine synapses and long-term potentiation can no longer be induced. The effects of hippocampal estrogen are of an auto-/paracrine nature, and are mediated via the known estrogen receptor subtypes ERα and ERβ. The regulation of hippocampal estrogen synthesis is mediated via GnRH and explains the correlation between spine synapse density and the female genital cycle, which is specific to the hippocampus.
|Number of pages||8|
|Publication status||Published - Nov 2007|
- Synaptic plasticity
ASJC Scopus subject areas