Quantitative analysis of kynurenine aminotransferase II in the adult rat brain reveals high expression in proliferative zones and corpus callosum
| Autor: | Kelley J. Murphy, Chang Song, Robert Schwarcz, Leonardo H. Tonelli, James D. Nicholson, Sarah M. Clark, Chloe N. Vaughn, Gloria E. Hoffman, Ta-Chung M. Mou |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Male Aging Kynurenine pathway Doublecortin Protein Rostral migratory stream Hippocampus Subventricular zone In situ hybridization Article 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Kynurenic acid Gene expression medicine Animals Rats Wistar Transaminases biology General Neuroscience Brain Kynurenine aminotransferase II Molecular biology Rats 030104 developmental biology medicine.anatomical_structure chemistry nervous system Astrocytes Female biology.gene Neuroscience 030217 neurology & neurosurgery |
| Popis: | Kynurenic acid, a metabolite of the kynurenine pathway of tryptophan degradation, acts as an endogenous antagonist of alpha7 nicotinic and NMDA receptors and is implicated in a number of neurophysiological and neuropathological processes including cognition and neurodegenerative events. Therefore, kynurenine aminotransferase II (KAT II/AADAT), the enzyme responsible for the formation of the majority of neuroactive kynurenic acid in the brain, has prompted significant interest. Using immunohistochemistry, this enzyme was localized primarily in astrocytes throughout the adult rat brain, but detailed neuroanatomical studies are lacking. Here, we employed quantitative in situ hybridization to analyze the relative expression of KAT II mRNA in the brain of rats under normal conditions and 6 h after the administration of lipopolysaccharides (LPSs). Specific hybridization signals for KAT II were detected, with the highest expression in the subventricular zone (SVZ), the rostral migratory stream and the floor of the third ventricle followed by the corpus callosum and the hippocampus. This pattern of mRNA expression was paralleled by differential protein expression, determined by serial dilutions of antibodies (up to 1:1 million), and was confirmed to be primarily astrocytic in nature. The mRNA signal in the SVZ and the hippocampus was substantially increased by the LPS treatment without detectable changes elsewhere. These results demonstrate that KAT II is expressed in the rat brain in a region-specific manner and that gene expression is sensitive to inflammatory processes. This suggests an unrecognized role for kynurenic acid in the brain’s germinal zones. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|