Department of Pharmacology, Korea University College of Medicine, Seoul 136-701, Korea.
Korean J Physiol Pharmacol. 2008 Jun;12(3):117-23. doi: 10.4196/kjpp.2008.12.3.117. Epub 2008 Jun 30.
Although growth associated protein-43 (GAP-43) is known to play a significant role in the regulation of axonal growth and the formation of new neuronal connections in the hippocampus, there is only a few studies on the effects of acute stress on GAP-43 mRNA expression in the hippocampus. Moreover, the effects of repeated citalopram treatment on chronic mild stress (CMS)-induced changes in GAP-43 mRNA expression in the hippocampus have not been explored before. To explore this question, male rats were exposed to acute immobilization stress or CMS. Also, citalopram was given prior to stress everyday during CMS procedures. Acute immobilization stress significantly increased GAP-43 mRNA expression in all subfields of the hippocampus, while CMS significantly decreased GAP-43 mRNA expression in the dentate granule cell layer (GCL). Repeated citalopram treatment decreased GAP-43 mRNA expression in the GCL compared with unstressed controls, but this decrease was not further potentiated by CMS exposure. Similar decreases in GAP-43 mRNA expression were observed in CA1, CA3 and CA4 areas of the hippocampus only after repeated citalopram treatment in CMS-exposed rats. This result indicates that GAP-43 mRNA expression in the hippocampus may differently respond to acute and chronic stress, and that repeated citalopram treatment does not change CMS-induced decreases in GAP-43 mRNA expression in the GCL.
尽管生长相关蛋白-43（GAP-43）已知在调节海马体中的轴突生长和新神经元连接的形成中起着重要作用，但关于急性应激对海马体中 GAP-43mRNA 表达的影响的研究甚少。此外，以前尚未探讨重复西酞普兰治疗对慢性轻度应激（CMS）诱导的海马体中 GAP-43mRNA 表达变化的影响。为了探讨这个问题，雄性大鼠暴露于急性束缚应激或 CMS 下。此外，在 CMS 过程中，每天在应激前给予西酞普兰。急性束缚应激显著增加了海马体所有亚区的 GAP-43mRNA 表达，而 CMS 则显著降低了齿状回颗粒细胞层（GCL）中的 GAP-43mRNA 表达。与未受应激的对照组相比，重复西酞普兰治疗后，GCL 中的 GAP-43mRNA 表达降低，但 CMS 暴露并未进一步增强这种降低。仅在 CMS 暴露的大鼠中重复西酞普兰治疗后，在海马体的 CA1、CA3 和 CA4 区也观察到 GAP-43mRNA 表达的类似降低。这一结果表明，海马体中的 GAP-43mRNA 表达可能对急性和慢性应激有不同的反应，并且重复西酞普兰治疗不会改变 CMS 诱导的 GCL 中 GAP-43mRNA 表达的降低。
