Effects of cortical ischemia and postischemic environmental enrichment on hippocampal cell genesis and differentiation in the adult rat.
The study aimed to elucidate the effects of cortical ischemia and postischemic environmental enrichment on hippocampal cell genesis. A cortical infarct was induced by a permanent ligation of the middle cerebral artery distal to the striatal branches in 6-month-old spontaneously hypertensive rats. Bromodeoxyuridine (BrdU) was administered as 7 consecutive daily injections starting 24 hours after surgery and animals were housed in standard or enriched environment. Four weeks after completed BrdU administration, BrdU incorporation and its co-localization with the neuronal markers NeuN and calbindin D28k, and the astrocytic marker glial fibrillary acidic protein in the granular cell layer and subgranular zone of the hippocampal dentate gyrus were determined with immunohistochemistry and were quantified stereologically. Compared with sham-operated rats, rats with cortical infarcts had a five-to sixfold ipsilateral increase in BrdU-labeled cells. About 80% of the new cells were neurons. Differential postischemic housing did not influence significantly the total number of surviving BrdU-labeled cells or newborn neurons. However, postischemic environmental enrichment increased the ipsilateral generation of astrocytes normalizing the astrocyte-to-neuron ratio, which was significantly reduced in rats housed in standard environment postischemically.
Komitova
Mila
M
Institute of Clinical Neuroscience, University of Göteborg, Sweden.
Perfilieva
Ekaterina
E
Mattsson
Bengt
B
Eriksson
Peter S
PS
Johansson
Barbro B
BB
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000737:chemistry / Q000473:pathology; D015415:Biomarkers / Q000032:analysis; D020520:Brain Infarction / Q000473:pathology; D002545:Brain Ischemia / Q000473:pathology*; D001973:Bromodeoxyuridine / Q000032:analysis / Q000378:metabolism; D064092:Calbindin 1; D064026:Calbindins; D002454:Cell Differentiation; D005455:Fluorescent Antibody Technique; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006624:Hippocampus / Q000473:pathology*; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000737:chemistry / Q000473:pathology; D010641:Phenotype; D051381:Rats; D011918:Rats, Inbred SHR; D064030:S100 Calcium Binding Protein G / Q000032:analysis
D015415:Biomarkers; C576500:Calb1 protein, rat; D064092:Calbindin 1; D064026:Calbindins; D005904:Glial Fibrillary Acidic Protein; D064030:S100 Calcium Binding Protein G; D001973:Bromodeoxyuridine