Progesterone regulation of synaptic transmission and plasticity in rodent hippocampus.
Ovarian hormones influence memory formation by eliciting changes in neural activity. The effects of various concentrations of progesterone (P4) on synaptic transmission and plasticity associated with long-term potentiation (LTP) and long-term depression (LTD) were studied using in vitro hippocampal slices. Extracellular studies show that the highest concentration of P4 tested (10(-6) M) decreased the baseline synaptic transmission and magnitude of LTP, but did not affect LTD. Intracellular studies suggest the P4 effect to be mediated, at least in part, by GABA(A) activity. These results establish a general effect of P4 on synaptic transmission, multiple forms of synaptic plasticity, and a possible mechanism of P4 action in hippocampus.
Foy
Michael R
MR
Department of Psychology, Loyola Marymount University, Los Angeles, California 90045, USA. mfoy@lmu.edu
Akopian
Garnik
G
Thompson
Richard F
RF
D000818:Animals; D001703:Biophysics; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation / Q000379:methods; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D006624:Hippocampus / Q000166:cytology* / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D009473:Neuronal Plasticity / Q000187:drug effects*; D010052:Ovariectomy / Q000379:methods; D018408:Patch-Clamp Techniques; D011374:Progesterone / Q000494:pharmacology*; D011372:Progestins / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects*
D018691:Excitatory Amino Acid Antagonists; D011372:Progestins; D011963:Receptors, GABA-A; D011374:Progesterone