Hayashi M, Yamashita A, Shimizu K
Department of Cellular and Molecular biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan.
Brain Res. 1997 Feb 28;749(2):283-9. doi: 10.1016/S0006-8993(96)01317-0.
The expression of the genes for somatostatin (SRIF) and brain-derived neurotrophic factor (BDNF) was investigated in the central nervous system (CNS) of the macaque monkey (Macaca fuscata fuscata). Using Northern blot analysis, one SRIF mRNA transcript, 0.65 kb, and two BDNF mRNA transcripts, 1.6 and 4.0 kb in length, were detected in the monkey brain tissues. During the aging process (2 years, 10 years, and > 30 years), the ratio of SRIF mRNA/glyceraldehyde-3 phosphate dehydrogenase (G3PDH) mRNA significantly decreased (60-70%) in the hippocampus and in several cerebral subdivisions such as frontal cortex, temporal cortex, motor cortex, somatosensory cortex and visual cortex. BDNF mRNA was expressed in the various cerebral subdivisions and in the hippocampus. During the aging process, the gene expression of BDNF declined (20-50% for the 4.0 kb transcript, and 40-70% for the 1.6 kb transcript) in the various cerebral subdivisions. In the hippocampus, the level of the 1.6 kb mRNA at > 30 years old declined to 60% of the level at 2 years old, while the 4.0 kb mRNA did not change significantly during the aging process. Recent studies have shown that BDNF enhances the expression of SRIF mRNA in the rodent cerebral cortex (Nawa, H. et al., J. Neurochem., 60 (1993) 772-775; Nawa, H. et al., J. Neurosci., 14 (1994) 3751-3765). These studies and our present results suggest that the decrease in gene expression for a neurotrophic molecule, such as BDNF, might cause the levels of SRIF mRNA to decline in the primate brain during the aging process.
在猕猴（日本猕猴指名亚种）的中枢神经系统（CNS）中研究了生长抑素（SRIF）和脑源性神经营养因子（BDNF）基因的表达。使用Northern印迹分析，在猴脑组织中检测到一种长度为0.65 kb的SRIF mRNA转录本和两种长度分别为1.6 kb和4.0 kb的BDNF mRNA转录本。在衰老过程中（2岁、10岁和>30岁），海马体以及额叶皮质、颞叶皮质、运动皮质、体感皮质和视觉皮质等几个脑区中，SRIF mRNA/甘油醛-3-磷酸脱氢酶（G3PDH）mRNA的比率显著下降（60-70%）。BDNF mRNA在各个脑区和海马体中均有表达。在衰老过程中，各个脑区中BDNF的基因表达下降（4.0 kb转录本下降20-50%，1.6 kb转录本下降40-70%）。在海马体中，>30岁时1.6 kb mRNA的水平下降至2岁时水平的60%，而4.0 kb mRNA在衰老过程中没有显著变化。最近的研究表明，BDNF可增强啮齿动物大脑皮质中SRIF mRNA的表达（Nawa, H.等人，《神经化学杂志》，60（1993）772-775；Nawa, H.等人，《神经科学杂志》，14（1994）3751-3765）。这些研究以及我们目前的结果表明，在衰老过程中，神经营养分子如BDNF的基因表达下降可能导致灵长类动物大脑中SRIF mRNA水平下降。
