Groth Rachel D, Weick Jason P, Bradley Katherine C, Luoma Jessie I, Aravamudan Bharathi, Klug Jason R, Thomas Mark J, Mermelstein Paul G
Department of Neuroscience, University of Minnesota, 6-145 Jackson Hall, 321 Church Street, S.E., Minneapolis, MN 55455, USA.
Eur J Neurosci. 2008 Jan;27(1):31-42. doi: 10.1111/j.1460-9568.2007.05980.x.
Exposure to drugs of abuse activates gene expression and protein synthesis that result in long-lasting adaptations in striatal signaling. Therefore, identification of the transcription factors that couple drug exposure to gene expression is of particular importance. Members of the nuclear factor of activated T-cells (NFATc) family of transcription factors have recently been implicated in shaping neuronal function throughout the rodent nervous system. Here we demonstrate that regulation of NFAT-mediated gene expression may also be a factor in drug-induced changes to striatal functioning. In cultured rat striatal neurons, stimulation of D1 dopamine receptors induces NFAT-dependent transcription through activation of L-type calcium channels. Additionally, the genes encoding inositol-1,4,5-trisphosphate receptor type 1 and glutamate receptor subunit 2 are regulated by striatal NFATc4 activity. Consistent with these in-vitro data, repeated exposure to cocaine triggers striatal NFATc4 nuclear translocation and the up-regulation of inositol-1,4,5-trisphosphate receptor type 1 and glutamate receptor subunit 2 gene expression in vivo, suggesting that cocaine-induced increases in gene expression may be partially mediated through activation of NFAT-dependent transcription. Collectively, these findings reveal a novel molecular pathway that may contribute to the enduring modifications in striatal functioning that occur following the administration of drugs of abuse.
滥用药物会激活基因表达和蛋白质合成,导致纹状体信号传导产生持久的适应性变化。因此,确定将药物暴露与基因表达联系起来的转录因子尤为重要。活化T细胞核因子(NFATc)家族的转录因子成员最近被认为在塑造整个啮齿动物神经系统的神经元功能中发挥作用。在此,我们证明NFAT介导的基因表达调控可能也是药物诱导纹状体功能变化的一个因素。在培养的大鼠纹状体神经元中,D1多巴胺受体的刺激通过L型钙通道的激活诱导NFAT依赖性转录。此外,编码1,4,5-三磷酸肌醇受体1型和谷氨酸受体亚基2的基因受纹状体NFATc4活性调控。与这些体外数据一致,反复接触可卡因会触发纹状体NFATc4核转位以及体内1,4,5-三磷酸肌醇受体1型和谷氨酸受体亚基2基因表达上调,这表明可卡因诱导的基因表达增加可能部分通过NFAT依赖性转录的激活介导。总的来说,这些发现揭示了一条新的分子途径,可能有助于解释滥用药物后纹状体功能发生的持久改变。