title: Cyclical changes in endogenous levels of oestrogen modulate the induction of LTD and LTP in the hippocampal CA1 region.
abstract: The present study investigated the effects of naturally fluctuating endogenous levels of oestrogen on the induction and maintenance of long-term potentiation (LTP) and long-term depression (LTD) in the CA1 region of the hippocampus. Using an anaesthetized in vivo preparation, the results showed that the induction of LTP was augmented during the pro-oestrous stage of the oestrous cycle. In contrast to LTP, however, the induction of paired-pulse LTD was severely attenuated during pro-oestrous, but was clearly manifested by rats during met/dioestrous and oestrous stages of the cycle. These findings are discussed with reference to: (i) the modulatory effects of oestrogen on N-methyl-D-aspartate (NMDA) receptor function and gamma-aminobutyric acid (GABA) neurotransmission in the hippocampus; and (ii) the functional implications that such cyclical changes in synaptic plasticity have for learning and memory processes supported by the hippocampus.
authors.affiliation: School of Psychology, Cardiff University, UK.
authors.forename: M
authors.initials: M
authors.lastname: Good
authors.forename: M
authors.initials: M
authors.lastname: Day
authors.forename: J L
authors.initials: JL
authors.lastname: Muir
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D004967:Estrogens / Q000378:metabolism*; D004971:Estrus / Q000502:physiology; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004967:Estrogens