Estrogen priming affects active membrane properties of medial amygdala neurons.
The medial nucleus of the amygdala (MNA) in the rat is a target tissue for estrogen binding and a sexually dimorphic structure. We used an in vivo slice preparation and intracellular recording techniques to study the effects of beta-estradiol priming on active and passive membrane properties of MNA neurons. Two groups of adult female rats were used; ovariectomized (OVX) non-primed rats and OVX rats that were estrogen-primed at least 24 h prior to recording. Estrogen priming increased the occurrence of spontaneous excitatory postsynaptic potentials (EPSPs) in MNA neurons, and of depolarizing afterpotentials (DAPs) observed with a cathodally triggered action potential, and was associated with a lack of accommodation in these cells. Overall, long-term exposure to estrogen markedly increased the spontaneous activity and excitability of the MNA neurons.
Schiess
M C
MC
Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston 77550.
Joëls
M
M
Shinnick-Gallagher
P
P
D000200:Action Potentials / Q000187:drug effects; D000679:Amygdala / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D004958:Estradiol / Q000008:administration & dosage*; D005260:Female; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D010052:Ovariectomy; D051381:Rats; D011919:Rats, Inbred Strains
D004958:Estradiol