Temporal change in NMDA receptor signaling and GABA_A receptor exypression in rat caudal vestibular nucleus during motion sickness habituation

详细信息	查看全文 | 推荐本文 |

• 作者：Jun-Qin Wang ; Hong-Xia Li¹ ; Xin-Min Chen ; Feng-Feng Mo ; Rui-Rui Qi ; Jun-Sheng Guo ; ^{guojs@shhyy.com} ; Yi-Ling Cai ; ^{yilingcai1@sohu.com}
• 关键词：NMDA ; N-methyl-d-aspartate ; CaMKII ; calmodulin protein kinase II ; CREB ; cAMP response element-binding ; GABA ; 纬-aminobutyric acid ; MVe ; medial vestibular nucleus ; SpVe ; spinal vestibular nucleus ; BDNF ; brain-derived neurotrophic factor ; LTP ; long-term pot
• 刊名：Brain Research
• 出版年：2012
• 期刊代码：8_00068993
• 类别：neu
• 出版时间：21 June, 2012
• 卷：1461
• 期：Complete
• 页码：30-40
• 文件大小：949 K

摘要

Repeated exposure to a provocative motion stimulus leads to motion sickness habituation indicative of the existence of central processes to counteract the disturbing properties of the imposed motion. In the present study, we attempt to investigate whether NMDA and GABA_A receptors in rat caudal vestibular nucleus neurons are involved in motion sickness habituation induced by repeated Ferris-wheel like rotation in daily session (2 h/d). We showed that defecation response increased and spontaneous locomotion decreased within 4 sessions (sickness phase). They recovered back to the control level after 7 sessions (habituation phase). Western blot analysis found that NMDA receptor signal molecules: calmodulin protein kinase II and cAMP response element-binding protein (CREB) were both activated during sickness phase, while a prolonged CREB activation was also observed during habituation phase. Real-time quantitative PCR revealed an increase in c-fos and a decrease in Arc mRNA level during sickness phase. We also found an increase in GABA_A receptor 伪1 subunit (GABA_A 伪1) protein level in this stage. These results suggested that altered NMDA receptor signaling and GABA_A receptor expression level in caudal vestibular nucleus were associated with motion sickness habituation. Furthermore, immunofluorescence and confocal laser scanning microscopy showed that the number of GABA_A 伪1 immunolabeled neurons in caudal vestibular nucleus increased while the number of GABA_A 伪1/Arc double labeled neurons and the average amount of Arc particle in soma of these neurons decreased during sickness phase. It suggested that GABA_A receptor level might be negatively regulated by Arc protein in caudal vestibular nucleus neurons.