Li Fei, Zhang Yuan-Yuan, Jing Xin-Ming, Yan Cong-Huai, Shen Xiao-Ming
Child Primary Care Department of Shanghai Children's Medical Center, Shanghai Jiao Tung University School of Medicine, Shanghai, China.
Neurosci Res. 2009 Jan;63(1):17-23. doi: 10.1016/j.neures.2008.09.008. Epub 2008 Oct 5.
This study examined the effects of early palmar forepaw sensorimotor deprivation on learning and memory in rats. Sensorimotor deprivation was performed on 18-day-old male rats. Controls were sham operated. Studies were performed on rats aged 18, 25, 35, 45 and 60 days. Morris water maze testing was used to assess learning and memory. Long-term potentiation (LTP) was assessed by electrophysiological means in slices obtained from the hippocampal Schaffer collateral pathway. Nissl staining was performed to assess pyramidal cell number in hippocampal CA1 and CA3 regions. Hippocampal N-methyl-d-aspartate receptor 1 (NMDAR1) mRNA and protein levels were assessed. Learning and short-term memory were significantly depressed in 25 and 35 day old sensorimotor deprived rats (P<0.01). LTP was also significantly depressed in sensorimotor deprived rats at these ages, while hippocampal CA1 pyramidal cell counts were significantly decreased (P<0.05). CA3 cell numbers were significantly lower in 25-day-old sensorimotor deprived rats (P<0.05). Both NMDAR1 mRNA and protein levels were significantly lower in sensorimotor deprived rats aged 25 and 35 days (P<0.05). These findings indicate that palmar surface forepaw sensorimotor deprivation impairs subsequent learning and memory in young rats. Decreased hippocampal pyramidal cell numbers and altered NMDAR1 expression may underlie this impairment.
本研究考察了早期掌部前爪感觉运动剥夺对大鼠学习和记忆的影响。对18日龄雄性大鼠进行感觉运动剥夺。对照组进行假手术。对18、25、35、45和60日龄的大鼠进行研究。采用莫里斯水迷宫测试评估学习和记忆。通过电生理方法在海马体谢弗侧支通路获取的脑片中评估长时程增强（LTP）。进行尼氏染色以评估海马CA1和CA3区锥体细胞数量。评估海马N-甲基-D-天冬氨酸受体1（NMDAR1）的mRNA和蛋白水平。在25和35日龄的感觉运动剥夺大鼠中，学习和短期记忆显著受损（P<0.01）。在这些年龄段的感觉运动剥夺大鼠中，LTP也显著受损，而海马CA1区锥体细胞数量显著减少（P<0.05）。在25日龄的感觉运动剥夺大鼠中，CA3区细胞数量显著降低（P<0.05）。在25和35日龄的感觉运动剥夺大鼠中，NMDAR1的mRNA和蛋白水平均显著降低（P<0.05）。这些发现表明，掌部前爪感觉运动剥夺会损害幼鼠随后的学习和记忆。海马锥体细胞数量减少和NMDAR1表达改变可能是这种损害的基础。
