Acute and chronic changes in the hippocampus after spinal cord injury

JUAN MANUEL ENCINAS; FLORENCIA LABOMBARDA; IGNACIO JURE; DE NICOLA ALEJANDRO FEDERICO

Buenos Aires

Simposio; Simposio Glia Polo Científico y Tecnologico; 2017

In previous works we have describedhippocampal alterations including neurogenesis reduction after chronic spinalcord injury in Sprague Dawley rats. These alterations become relevant sincespinal cord injury patients exhibit cognitive deficits that may be related withthe alterations in the hippocampus. In the present work we used the Nestin-GFPmice in a BrDU and Ki67 approach to assess the radial glia and amplifyingprogenitors survival and mitotic capacity after acute and chronic spinal cordinjury. We also perform a histological evaluation of the astrocytes andmicroglia in different hippocampus sub regions. In the acute period we observe a reductionin doublecortin, and ki67 cells in the dentate gyrus. We also find decrees inthe number of cFos cells in this region indicating alterations in the activitythat may be related with the reduced neurogenesis. Fifty days after injury theanimals exhibit a reduction in the BrDU-nestin cells in the dentate gyrusindicating a decrease in the survival of newborn neurons.   Moreover, in the chronic phase the animalsmaintain the cFos positive cells reduction indicating irreversible changes inthe neuronal activity of the dentate gyrus. Finally there?s a  activation in the astrocytes of differentregions of the hippocampus that is specially prominent in de stratumradiatum.