scholarly journals Age-Related Deficits in Spatial Memory and Hippocampal Spines in Virgin, Female Fischer 344 Rats

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Victoria N. Luine ◽  
Maureen E. Wallace ◽  
Maya Frankfurt
Keyword(s):  
Spatial Memory ◽  
Dendritic Spine ◽  
Pyramidal Neurons ◽  
Female Rats ◽  
Spine Density ◽  
Fischer 344 ◽  
Dendritic Spine Density ◽  
Basal Dendrites ◽  
Young Subjects ◽  
Aged Subjects

Effects of aging on memory and brain morphology were examined in aged, 21-month-old, and young, 4-month-old, Fischer 344 female rats. Spatial memory was assessed using the object placement task, and dendritic spine density was determined on pyramidal neurons in the hippocampus following Golgi impregnation. Consistent with previous studies, aged females showed poorer object placement performance than young subjects. Young subjects significantly discriminated the location of objects with a 1.5-hour intertrial delay while aged subjects did not. Spine density of basal dendrites on CA1 pyramidal cells was 16% lower in the aged subjects as compared to the young subjects. No differences in spine density were found between young and aged subjects in basal dendrites of CA1 or in either dendritic field of CA3 pyramidal neurons. Thus, decreased hippocampal CA1 dendritic spine density in aged rats may contribute to poorer spatial memory as compared to young rats. The possibility that the neuroplastic changes observed in this study may pertain only to female subjects having had a specific set of life experiences is discussed. Different factors, such as reproductive status, diet, and handling may contribute to neuroplasticity of the brain during aging; however, this view requires further examination.

Dendritic Spine Density of Pyramidal Neurons in Field CA1 of the Hippocampus Decreases due to Chronic Tryptophan Restriction

1998 ◽  
Vol 1 (3) ◽  
pp. 237-242 ◽  
Author(s):  
M.I. Pérez-Vega ◽  
G. Barajas-López ◽  
A.R. del Angel-Meza ◽  
I. González-Burgos ◽  
A. Feria-Velasco
Keyword(s):  
Dendritic Spine ◽  
Pyramidal Neurons ◽  
Spine Density ◽  
Dendritic Spine Density ◽  
Field Ca1

scholarly journals Hippocampal CA1 Pyramidal Neurons ofMecp2Mutant Mice Show a Dendritic Spine Phenotype Only in the Presymptomatic Stage

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Christopher A. Chapleau ◽  
Elena Maria Boggio ◽  
Gaston Calfa ◽  
Alan K. Percy ◽  
Maurizio Giustetto ◽  
...  
Keyword(s):  
Dendritic Spines ◽  
Dendritic Spine ◽  
Pyramidal Neurons ◽  
Mutant Mice ◽  
Spine Density ◽  
Ca1 Pyramidal Neurons ◽  
Dendritic Spine Density ◽  
Presymptomatic Stage ◽  
Deficient Mice

Alterations in dendritic spines have been documented in numerous neurodevelopmental disorders, including Rett Syndrome (RTT). RTT, an X chromosome-linked disorder associated with mutations inMECP2, is the leading cause of intellectual disabilities in women. Neurons inMecp2-deficient mice show lower dendritic spine density in several brain regions. To better understand the role of MeCP2 on excitatory spine synapses, we analyzed dendritic spines of CA1 pyramidal neurons in the hippocampus ofMecp2tm1.1Jaemale mutant mice by either confocal microscopy or electron microscopy (EM). At postnatal-day 7 (P7), well before the onset of RTT-like symptoms, CA1 pyramidal neurons from mutant mice showed lower dendritic spine density than those from wildtype littermates. On the other hand, at P15 or later showing characteristic RTT-like symptoms, dendritic spine density did not differ between mutant and wildtype neurons. Consistently, stereological analyses at the EM level revealed similar densities of asymmetric spine synapses in CA1stratum radiatumof symptomatic mutant and wildtype littermates. These results raise caution regarding the use of dendritic spine density in hippocampal neurons as a phenotypic endpoint for the evaluation of therapeutic interventions in symptomaticMecp2-deficient mice. However, they underscore the potential role of MeCP2 in the maintenance of excitatory spine synapses.

scholarly journals Bisphenol-A exposure during adolescence leads to enduring alterations in cognition and dendritic spine density in adult male and female rats

2015 ◽  
Vol 69 ◽  
pp. 89-97 ◽  
Author(s):  
Rachel E. Bowman ◽  
Victoria Luine ◽  
Samantha Diaz Weinstein ◽  
Hameda Khandaker ◽  
Sarah DeWolf ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Adult Male ◽  
Dendritic Spine ◽  
Female Rats ◽  
Spine Density ◽  
Male And Female ◽  
Dendritic Spine Density ◽  
Male And Female Rats

scholarly journals Developmental Stage-dependent Persistent Impact of Propofol Anesthesia on Dendritic Spines in the Rat Medial Prefrontal Cortex

2011 ◽  
Vol 115 (2) ◽  
pp. 282-293 ◽  
Author(s):  
Adrian Briner ◽  
Irina Nikonenko ◽  
Mathias De Roo ◽  
Alexandre Dayer ◽  
Dominique Muller ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Prefrontal Cortex ◽  
Developmental Stage ◽  
Medial Prefrontal Cortex ◽  
Dendritic Spine ◽  
Pyramidal Neurons ◽  
Postnatal Life ◽  
Spine Density ◽  
Quantitative Electron Microscopy ◽  
Dendritic Spine Density

Background Recent observations demonstrate that anesthetics rapidly impair synaptogenesis during neuronal circuitry development. Whether these effects are lasting and depend on the developmental stage at which these drugs are administered remains, however, to be explored. Methods Wistar rats received propofol anesthesia at defined developmental stages during early postnatal life. The acute and long-term effects of these treatments on neuronal cytoarchitecture were evaluated by Neurolucida and confocal microscopy analysis after iontophoretic injections of Lucifer Yellow into layer 5 pyramidal neurons in the medial prefrontal cortex. Quantitative electron microscopy was applied to investigate synapse density. Results Layer 5 pyramidal neurons of the medial prefrontal cortex displayed intense dendritic growth and spinogenesis during the first postnatal month. Exposure of rat pups to propofol at postnatal days 5 and 10 significantly decreased dendritic spine density, whereas this drug induced a significant increase in spine density when administered at postnatal days 15, 20, or 30. Quantitative electron microscopy revealed that the propofol-induced increase in spine density was accompanied by a significant increase in the number of synapses. Importantly, the propofol-induced modifications in dendritic spine densities persisted up to postnatal day 90. Conclusion These new results demonstrate that propofol anesthesia can rapidly induce significant changes in dendritic spine density and that these effects are developmental stage-dependent, persist into adulthood, and are accompanied by alterations in synapse number. These data suggest that anesthesia in the early postnatal period might permanently impair circuit assembly in the developing brain.

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