Ischemia-induced changes in monocarboxylate transporter 1 reactive cells in rat hippocampus

This study aims to demonstrate the responses of monocarboxylate transporter 1 (MCT1) immunoreactive cells to transient global ischemia in rat hippocampus using confocal and electron microscopy. The MCT1 staining in CA1 pyramidal cells of the sham-operated controls appeared evenly distributed. Most of the MCT1 immunoreactive products were associated with the cell surface; however, some intracellular reaction products are also found. This pattern of stain was not altered in the first three days after an ischemic episode. As the neuronal demise progressed, the MCT1 immunoreactive cells became patchy in the 21-day post-ischemic rats. Besides the neuronal labeling, MCT1 immunoreactivity was found in astroglia, in endothelial cells and in the adjacent ependymal lining. The latter exhibited intense labeling both in the acute and long-term surviving rats. These data suggest that MCT1 plays a role in the initial and long-term neuronal survival in the hippocampus.