| Autor: |
Mary C, McKenna, Malin H, Stridh, Laura F, McNair, Ursula, Sonnewald, Helle S, Waagepetersen, Arne, Schousboe |
| Rok vydání: |
2016 |
| Předmět: |
|
| Zdroj: |
Journal of neuroscience research. 94(12) |
| ISSN: |
1097-4547 |
| Popis: |
The cellular distribution of transporters and enzymes related to glutamate metabolism led to the concept of the glutamate-glutamine cycle. Glutamate is released as a neurotransmitter and taken up primarily by astrocytes ensheathing the synapses. The glutamate carbon skeleton is transferred back to the presynaptic neurons as the nonexcitatory amino acid glutamine. The cycle was initially thought to function with a 1:1 ratio between glutamate released and glutamine taken up by neurons. However, studies of glutamate metabolism in astrocytes have shown that a considerable proportion of glutamate undergoes oxidative degradation; thus, quantitative formation of glutamine from the glutamate taken up is not possible. Oxidation of glutamate is initiated by transamination catalyzed by an aminotransferase, or oxidative deamination catalyzed by glutamate dehydrogenase (GDH). We discuss methods available to elucidate the enzymes that mediate this conversion. Methods include pharmacological tools such as the transaminase inhibitor aminooxyacetic acid, studies using GDH knockout mice, and siRNA-mediated knockdown of GDH in astrocytes. Studies in brain slices incubated with [ |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Plný text