The evolving role of dendritic spines and memory: Interaction(s) with estradiol

Abstract

This article is part of a Special Issue "Estradiol and Cognition". Memory processing is presumed to depend on synaptic plasticity, which appears to have a role in mediating the acquisition, consolidation, and retention of memory. We have studied the relationship between estrogen, recognition memory, and dendritic spine density in the hippocampus and medial prefrontal cortex, areas critical for memory, across the lifespan in female rodents. The present paper reviews the literature on dendritic spine plasticity in mediating both short and long term memory, as well as the decreased memory that occurs with aging and Alzheimer's disease. It also addresses the role of acute and chronic estrogen treatments in these processes.

Keywords: Dendritic spines; Estradiol; Estrogen; Hippocampus; Memory; Prefrontal cortex; Synaptic plasticity.

Figure 1

A. Schematic coronal section illustrating the region of the medial prefrontal cortex of the rat examined in Golgi preparations. B. Golgi impregnated pyramidal neurons from layer ll/lll and V of the medial prefrontal cortex (10×). C. Representative pyramidal cells from medial prefrontal cortex. Arrows denote the secondary basal and tertiary apical dendrites used for analysis (20×).

Figure 2

A: Schematic coronal section illustrating the CA1 region of the rat hippocampus examined in Golgi preparations. B. Golgi impregnated pyramidal neurons from CA1 (10×). C. Representative dendrite used to count spines (denoted by arrows, 100× under oil).