NMDA receptor stimulation selectively initiates GABA(A) receptor delta subunit mRNA expression in cultured rat cerebellar granule neurons.
NMDA receptor stimulation selectively initiates GABA(A) receptor delta subunit mRNA expression in cultured rat cerebellar granule neurons.
复制标题
NMDA 受体刺激选择性启动培养的大鼠小脑颗粒神经元中 GABA(A) 受体 δ 亚基 mRNA 的表达。
DOI：
10.1046/j.1471-4159.1998.70051907.x
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发表时间：
1998
影响因子：
4.7
通讯作者：
Siegel,RE
中科院分区：
文献类型：
--
作者：
Gault,LM;Siegel,RE
Findings in vivo and in culture suggest that neuronal activity selectively regulates GABAAreceptor δ subunit mRNA expression in cerebellar granule neurons. For example, the onset of δ subunit mRNA expression during postnatal maturation coincides with innervation. Furthermore, depolarizing conditions (25 mMKCl) in culture initiate and maintain increases in the δ subunit transcript level. We have now examined whether similar changes in δ subunit mRNA expression occur in cultured neurons after activation of glutamate receptors of the NMDA subtype, an event that mimics granule neuron depolarization by mossy fiber innervation in vivo. Our studies demonstrate that addition of 50 µMNMDA to cultured rat granule neurons maintained in defined, serum‐free medium specifically initiates δ subunit transcript expression. Whereas the level of the δ subunit mRNA is increased fourfold by this treatment, levels of other GABAAreceptor subunit transcripts are not significantly changed. The level of the δ subunit transcript is further increased when NMDA receptor activation is enhanced by maintaining neurons in a Mg2+‐free medium to alleviate Mg2+blockade of the receptor channel. The NMDA‐induced elevation in δ subunit transcript expression involves activation of a Ca2+/calmodulin‐dependent protein kinase pathway. These findings suggest that activation of an excitatory pathway may regulate the expression of an inhibitory receptor phenotype in cerebellar granule neurons in vivo.
