Department of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Meijo University, Nagoya, 468-8503, Japan.
Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, 466-8560, Japan.
Psychopharmacology (Berl). 2017 Oct;234(20):3055-3074. doi: 10.1007/s00213-017-4704-8. Epub 2017 Jul 29.
Stress during the adolescent period influences postnatal maturation and behavioral patterns in adulthood. Adolescent stress-induced molecular and functional changes in neurons are the key clinical features of psychiatric disorders including schizophrenia.
In the present study, we exposed genetically vulnerable mice to isolation stress to examine the molecular changes in the glutamatergic system involving N-methyl-d-aspartate (NMDA) receptors via dopaminergic disturbance in the prefrontal cortex (PFc).
We report that late adolescent stress in combination with Disrupted-in-Schizophrenia 1 (DISC1) genetic risk elicited alterations in glutamatergic neurons in the PFc, such as increased expression of glutamate transporters, decreased extracellular levels of glutamate, decreased concentration of d-serine, and impaired activation of NMDA-Ca/calmodulin kinase II signaling. These changes resulted in behavioral deficits in locomotor activity, forced swim, social interaction, and novelty preference tests. The glutamatergic alterations in the PFc were prevented if the animals were treated with an atypical antipsychotic drug clozapine and a dopamine D1 agonist SKF81297, which suggests that the activation of dopaminergic neurons is involved in the regulation of the glutamatergic system.
Our results suggest that adolescent stress combined with dopaminergic abnormalities in the PFc of genetically vulnerable mice induces glutamatergic disturbances, which leads to behavioral deficits in the young adult stage.
青春期的压力会影响成年后的产后成熟和行为模式。青少年应激引起的神经元分子和功能变化是包括精神分裂症在内的精神障碍的关键临床特征。
本研究通过前额叶皮质(PFc)中的多巴胺能干扰,使遗传易感性的小鼠暴露于隔离应激下,以检查涉及 N-甲基-D-天冬氨酸(NMDA)受体的谷氨酸能系统的分子变化。
我们报告说,青春期后期的应激与精神分裂症 1 号(DISC1)遗传风险相结合,导致 PFc 中的谷氨酸能神经元发生变化,如谷氨酸转运体表达增加、细胞外谷氨酸水平降低、d-丝氨酸浓度降低以及 NMDA-Ca/钙调蛋白激酶 II 信号转导受损。这些变化导致动物在运动活动、强迫游泳、社会互动和新奇偏好测试中的行为缺陷。如果用非典型抗精神病药物氯氮平和多巴胺 D1 激动剂 SKF81297 治疗动物,则可以预防 PFc 中的谷氨酸能变化,这表明多巴胺能神经元的激活参与了谷氨酸能系统的调节。
我们的研究结果表明,青春期应激与遗传易感性小鼠 PFc 中的多巴胺能异常相结合,会导致谷氨酸能紊乱,从而导致年轻成年期的行为缺陷。