Table 1 Summary of the effects of estrogens on hippocampal dendritic spine density
From: Structural plasticity of the hippocampus in response to estrogens in female rodents
Reference | Model | Results |
|---|---|---|
Woolley et al., 1990 | Intact female rats | CA1 dendritic spine density fluctuates by approx. 30% across estrous cycle; highest densities when circulating estrogens are highest [50] |
Gould et al., 1990 | Intact and OVX female rats | OVX decreases CA1 dendritic spine density [49] |
Woolley & McEwen, 1992 | OVX female rats | 2 subcutaneous (s.c.) injections of EB (given 24h apart) reverse CA1 dendritic spine density decreases from OVX within 48h following second injection [51] |
Woolley & McEwen, 1993 | OVX female rats | S.c. EB or 17β-estradiol increases CA1 pyramidal neuron apical dendritic spine density within 24h, peaked at 2-3d, declines over 7d; s.c. progesterone following 17β-estradiol further increased spine density for 2-6h but then levels fell quickly to baseline [52] |
Leranth et al., 2003 | Intact and GDX male rats | GDX reduces CA1 spine synapse density; s.c. testosterone proprionate increases CA1 spine synapse density in intact males after 2d of treatment; s.c. dihydrotestosterone but not 17β-estradiol increased CA1 spine synapse density in GDX males after 2d of treatment [55] |
MacLusky et al., 2004 | Intact male rats | Increases in CA1 dendritic spine density driven by s.c. testosterone are not via aromatization of testosterone to estrogens [56] |
MacLusky et al., 2005 | OVX female rats | S.c. 17β-estradiol increases CA1 spine synapse density within 30min and 4.5h; s.c. 17α-estradiol increases CA1 spine synapse density within 30min [63] |
Tsurugizawa et al., 2005 | Ex vivo hippocampal slices from male rats | 2h bath in 17β-estradiol or ERα agonist decreased CA3 dendritic excrescence thorns [95] |
Kinsley et al., 2006 | Intact, pregnant, lactating, and OVX female rats | Pregnant and lactating rats had greater CA1 dendritic spine density than nulliparous intact rats; nulliparous proestrus intact rats had greater CA1 dendritic spine density than nulliparous diestrus or estrus intact rats; OVX rats given hormonal treatment to mimic pregnancy (17β-estradiol and progesterone via Silastic implant) had greater CA1 dendritic spine density than OVX controls [135] |
Murakami et al., 2006 | Ex vivo hippocampal slices from male rats | Increased CA1 stratum oriens or lacunosum-moleculare dendritic spine density following 2h bath in 17β-estradiol or ERα agonist [64] |
Wallace et al., 2006 | Intact and OVX female rats | 7wks post-surgery, OVX rats had decreased CA1, but not CA3, dendritic spines compared to intact rats [136] |
Mukai et al., 2007 | Ex vivo hippocampal slices from male rats | Increased CA1 stratum radiatum dendritic spine density following 2h bath in 17β-estradiol or ERα agonist [65] |
Phan et al., 2011 | OVX female mice | S.c. ERα agonist increased CA1 spine density within 40min; s.c. ERβ agonist decreased spine density and increased spine length within 40min [38] |
González-Burgos et al., 2012 | Intact male rats | Injection of tamoxifen or raloxifene (route not specified) increased CA1 dendritic spine density; tamoxifen increased thin- and stubby-type spines whereas raloxifene increased thin-, stubby-, and wide-type spines [93] |
Phan et al., 2012 | OVX female mice | S.c. 17β-estradiol increased CA1 dendritic spine length within 40min [39] |
Velázquez-Zamora et al., 2012 | OVX female rats | Twice daily treatment (s.c.) with EB increased CA1 dendritic spine density at 3d, but not 10d [125] |
Gabor et al., 2015 | OVX female mice | S.c. GPER1 agonist increased CA1 dendritic spine density within 40min [41] |
Phan et al., 2015 | Ex vivo hippocampal slices from female mice | 17β-estradiol or ERα agonist increased CA1 dendritic spine density within 30min of bath application [40] |
Jacome et al., 2016 | GDX male rats | Acute s.c. injection of 17β-estradiol or T increased CA1, but not DG, dendritic spine density 30min or 2h following treatment [59] |
Tuscher et al., 2016 | OVX female mice | Intrahippocampal 17β-estradiol increased CA1 basal and apical dendritic spine density within 30min or 2h of treatment; intracerebroventricular 17β-estradiol increased CA1 basal and apical dendritic spine density within 2h via ERK and mTOR pathways [42] |
Mendell et al., 2017 | Intact and OVX female rats, intact and GDX male rats | Proestrus intact females had greater CA1 apical dendritic spine densities than metestrus intact or OVX females; proestrus intact females had greater CA3 apical dendritic spine densities than OVX females; GDX males had increased CA3 dendritic branching than intact males; OVX had minimal effects on dendritic branching [32] |