Cre recombinase mediated deletion of the NMDA receptor in dopamine neurons

Cre重组酶介导多巴胺神经元中NMDA受体的缺失

• 批准号: 7966949
• 负责人: Cristina Backman
• 金额: $ 41.74万
• 依托单位: NATIONAL INSTITUTE ON DRUG ABUSE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7966949
• 关键词: Agreement; Animals; Area; Bilateral; Brain; Cannulas; Cells; Chemosensitization; Cocaine; Data; Dopamine; Implant; Injection of therapeutic agent; Label; Laboratories; Lesion; Long-Term Potentiation; Mediating; Mediator of activation protein; Midbrain structure; Mus; N-Methyl-D-Aspartate Receptors; N-Methylaspartate; NR1 gene; Neurons; Paper; Peripheral; Pharmaceutical Preparations; Population; Prefrontal Cortex; Publishing; Reporting; Role; Synapses; Synaptic plasticity; Treatment Protocols; behavioral sensitization; cocaine exposure; dopamine system; dopaminergic neuron; mRNA Expression; patch clamp; receptor; recombinase; research study; response

DAT-NR1 KO mice were implanted with a bilateral cannula in the VTA to deliver specific NMDAR antagonists during a cocaine sensitization regimen, and our results have shown that sensitization can be equally blocked in DAT-NR1 KO and WT animals by simultaneous injection of an NMDAR antagonist in the VTA along with peripheral cocaine. Our experiments are now aimed at ruling out or including the mesocortical DA cell population as the mediator of VTA NMDA dependent sensitization. We are currently performing patch-clamp recordings from retrograde labeled neurons projecting to the prefrontal cortex in DAT-NR1 KO to determine if these dopamine neurons, due to low DAT levels and therefore lack of Cre, may express NMDAR currents. In addition, TH-NR1 KO animals are being generated, and if viable, will be used to determine the response to cocaine sensitization, as in these KO animals NMDAR currents will be eliminated in all dopamine cells. Possible pitfalls when using TH-NR1 animals is the unspecificity of the NR1 deletion, as NMDAR will be deleted in all cathecholaminergic brain areas. However, if TH-NR1 KO animals do not develop cocaine induced sensitization it will suggest the likelihood of an active role of the DA mesocortical projection for the initiation of sensitization.

DAT-NR1 KO mice were implanted with a bilateral cannula in the VTA to deliver specific NMDAR antagonists during a cocaine sensitization regimen, and our results have shown that sensitization can be equally blocked in DAT-NR1 KO and WT animals by simultaneous injection of an NMDAR antagonist in the VTA along with peripheral cocaine.现在，我们的实验旨在排除或包括中皮质DA细胞群，为VTA NMDA依赖性敏化的介体。目前，我们正在执行从逆行标记的神经元投射到dat-nr1 ko前额叶皮层的膜片钳记录，以确定由于较低的DAT级别并且缺乏CRE而可能表达NMDAR电流。另外，正在产生Th-NR1 KO动物，如果可行，将使用可卡因敏化的反应，因为在所有多巴胺细胞中将消除这些KO动物NMDAR电流。当使用Th-NR1动物时，可能会陷阱是NR1缺失的特异性，因为NMDAR将在所有呼吸道胺能大脑区域中删除。但是，如果TH-NR1 KO动物没有发展可卡因引起的敏化，则表明DA中皮层投射在开始敏化的可能性中起着积极作用。