Anterior thalamic lesions reduce spine density in both hippocampal CA1 and retrosplenial cortex, but enrichment rescues CA1 spines only

Hippocampus ◽  
2014 ◽  
Vol 24 (10) ◽  
pp. 1232-1247 ◽  
Author(s):  
Bruce C. Harland ◽  
David A. Collings ◽  
Neil McNaughton ◽  
Wickliffe C. Abraham ◽  
John C. Dalrymple-Alford
Keyword(s):  
Retrosplenial Cortex ◽  
Spine Density ◽  
Hippocampal Ca1 ◽  
Thalamic Lesions

scholarly journals Robust information routing by dorsal subiculum neurons

2021 ◽  
Vol 7 (11) ◽  
pp. eabf1913
Author(s):  
Takuma Kitanishi ◽  
Ryoko Umaba ◽  
Kenji Mizuseki
Keyword(s):  
Nucleus Accumbens ◽  
Large Scale ◽  
Dorsal Hippocampus ◽  
Retrosplenial Cortex ◽  
Projection Neurons ◽  
Target Region ◽  
Ca1 Neurons ◽  
Axonal Projections ◽  
Output Structure ◽  
Hippocampal Ca1

The dorsal hippocampus conveys various information associated with spatial navigation; however, how the information is distributed to multiple downstream areas remains unknown. We investigated this by identifying axonal projections using optogenetics during large-scale recordings from the rat subiculum, the major hippocampal output structure. Subicular neurons demonstrated a noise-resistant representation of place, speed, and trajectory, which was as accurate as or even more accurate than that of hippocampal CA1 neurons. Speed- and trajectory-dependent firings were most prominent in neurons projecting to the retrosplenial cortex and nucleus accumbens, respectively. Place-related firing was uniformly observed in neurons targeting the retrosplenial cortex, nucleus accumbens, anteroventral thalamus, and medial mammillary body. Theta oscillations and sharp-wave/ripples tightly controlled the firing of projection neurons in a target region–specific manner. In conclusion, the dorsal subiculum robustly routes diverse navigation-associated information to downstream areas.

scholarly journals Anterior thalamic lesions stop synaptic plasticity in retrosplenial cortex slices: expanding the pathology of diencephalic amnesia

Brain ◽  
2009 ◽  
Vol 132 (7) ◽  
pp. 1847-1857 ◽  
Author(s):  
D. L. F. Garden ◽  
P. V. Massey ◽  
D. A. Caruana ◽  
B. Johnson ◽  
E. C. Warburton ◽  
...  
Keyword(s):  
Synaptic Plasticity ◽  
Retrosplenial Cortex ◽  
Diencephalic Amnesia ◽  
Thalamic Lesions ◽  
Cortex Slices

scholarly journals EphB2 receptor cell-autonomous forward signaling mediates auditory memory recall and learning-driven spinogenesis

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Asghar Talebian ◽  
Mark Henkemeyer
Keyword(s):  
Auditory Cortex ◽  
Memory Loss ◽  
Kinase Domain ◽  
Auditory Memory ◽  
Tyrosine Kinase Domain ◽  
Memory Recall ◽  
Neural Activation ◽  
Spine Density ◽  
Synaptic Interactions ◽  
Hippocampal Ca1

Abstract While ephrin-B ligands and EphB receptors are expressed to high levels in the learning centers of the brain, it remains largely unknown how their trans-synaptic interactions contribute to memory. We find that EphB2 forward signaling is needed for contextual and sound-evoked memory recall and that constitutive over-activation of the receptor’s intracellular tyrosine kinase domain results in enhanced memory. Loss of EphB2 expression does not affect the number of neurons activated following encoding, although a reduction of neurons activated after the sound-cued retrieval test was detected in the auditory cortex and hippocampal CA1. Further, spine density and maturation was reduced in the auditory cortex of mutants especially in the neurons that were dual-activated during both encoding and retrieval. Our data demonstrates that trans-synaptic ephrin-B-EphB2 interactions and forward signaling facilitate neural activation and structural plasticity in learning-associated neurons involved in the generation of memories.

scholarly journals Comparative 2D and 3D Ultrastructural Analyses of Dendritic Spines from CA1 Pyramidal Neurons in the Mouse Hippocampus

2021 ◽  
Vol 22 (3) ◽  
pp. 1188
Author(s):  
Maria Nicol Colombo ◽  
Greta Maiellano ◽  
Sabrina Putignano ◽  
Lucrezia Scandella ◽  
Maura Francolini
Keyword(s):  
Pyramidal Neurons ◽  
Brain Connectivity ◽  
Three Dimensional ◽  
Excitatory Synapses ◽  
Spine Density ◽  
Functional Impairments ◽  
Small Complex ◽  
Hippocampal Ca1 ◽  
3D Em ◽  
2D And 3D

Three-dimensional (3D) reconstruction from electron microscopy (EM) datasets is a widely used tool that has improved our knowledge of synapse ultrastructure and organization in the brain. Rearrangements of synapse structure following maturation and in synaptic plasticity have been broadly described and, in many cases, the defective architecture of the synapse has been associated to functional impairments. It is therefore important, when studying brain connectivity, to map these rearrangements with the highest accuracy possible, considering the affordability of the different EM approaches to provide solid and reliable data about the structure of such a small complex. The aim of this work is to compare quantitative data from two dimensional (2D) and 3D EM of mouse hippocampal CA1 (apical dendrites), to define whether the results from the two approaches are consistent. We examined asymmetric excitatory synapses focusing on post synaptic density and dendritic spine area and volume as well as spine density, and we compared the results obtained with the two methods. The consistency between the 2D and 3D results questions the need—for many applications—of using volumetric datasets (costly and time consuming in terms of both acquisition and analysis), with respect to the more accessible measurements from 2D EM projections.

scholarly journals Chronic stress and a cyclic regimen of estradiol administration separately facilitate spatial memory: Relationship with hippocampal CA1 spine density and dendritic complexity.

2012 ◽  
Vol 126 (1) ◽  
pp. 142-156 ◽  
Author(s):  
Cheryl D. Conrad ◽  
Katie J. McLaughlin ◽  
Thu N. Huynh ◽  
Mariam El-Ashmawy ◽  
Michelle Sparks
Keyword(s):  
Spatial Memory ◽  
Chronic Stress ◽  
Spine Density ◽  
Hippocampal Ca1 ◽  
Dendritic Complexity
Sign in / Sign up

Export Citation Format

Share Document