Density, but not shape, of hippocampal dendritic spines varies after a seizure-inducing acute dose of monosodium glutamate in rats

doi:10.1016/j.neulet.2004.03.035

Neuroscience Letters

Volume 363, Issue 1, 3 June 2004, Pages 22-24

https://doi.org/10.1016/j.neulet.2004.03.035 Get rights and content

Abstract

Dendritic spines are the main postsynaptic neuronal targets of excitatory inputs in cortical neurons, and both spine density and shape possess a well known adaptive synaptic-stimulation-dependent plastic capacity. Eighteen Sprague–Dawley adult male rats were used. Monosodium glutamate-treated rats (4 g/kg of body weight, i.p.) showed tonic and clonic epileptic seizures, as well as less dendritic spines in the apical arborization of their hippocampal CA1 pyramidal cells, compared to both control groups. No changes were seen in the proportional density of thin, stubby, mushroom-shaped, wide, or ramified spines between groups. Excessive glutamate-mediated excitatory activity on receptors could have led dendritic spines to shrink until they disappeared, while the spine-type proportion may be kept balanced as an adaptive response.

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Density, but not shape, of hippocampal dendritic spines varies after a seizure-inducing acute dose of monosodium glutamate in rats

Abstract

Brain Res.

Prog. Neurobiol.

Brain Res.

Brain Res. Bull.

Brain Res.

Brain Res. Bull.

Cell death and synaptic reorganizations produced by seizures

Epilepsia

Golgi method without osmium tetroxide for the study of the central nervous system

Biotech. Histochem.

Calcium from internal stores modifies dendritic spine shape

Proc. Natl. Acad. Sci. USA