Dominance-related changes in spatial memory are associated with changes in hippocampal cell proliferation rates in mountain chickadees.
Dominance-related changes in spatial memory are associated with changes in hippocampal cell proliferation rates in mountain chickadees.
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空间记忆的优势相关变化与山雀海马细胞增殖率的变化有关。
DOI：
10.1002/neu.20065
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Omanska,Alicja
中科院分区：
文献类型：
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作者：
Pravosudov,VladimirV;Omanska,Alicja
哺乳动物和鸟类的空间记忆都依赖于海马体，这一点已经得到了很好的证实。由于记忆容量可以在时间基础上波动，因此了解调节这种变化的机制非常重要。众所周知，幼年动物的早期记忆依赖经历会导致海马增大和神经发生增加，包括细胞增殖和神经元存活。然而，目前尚不清楚的是，空间记忆的时间变化是否也与完全成熟和有经验的成年动物的海马解剖结构和细胞增殖的变化有关。在之前的一项研究中，我们通过实验证明，在皮质酮基线水平没有显著差异的情况下，社会地位较低的山山雀（Poecile gambeli）的空间记忆表现低于其优势群体同伴。在这里，我们研究了这些优势和从属鸟类之间的记忆差异是否与海马体的变化有关。在记忆测试后，给山雀注射5 -溴- 2 ' -脱氧尿苷来标记分裂细胞，并在注射后2天处死。我们发现优势和劣势山雀在海马形成的神经元体积和总数上没有显著差异，但劣势山雀在靠近海马和中蹼的心室区细胞增殖率明显低于优势山雀。在空间记忆测试中表现更好的个体往往有更高水平的细胞增殖。这些结果表明，社会地位可以影响心室区的细胞增殖速率，并支持神经发生可能参与成年动物记忆功能的假设。©2004 Wiley期刊公司神经生物学杂志，2005
It is well established that spatial memory is dependent on the hippocampus in both mammals and birds. As memory capacity can fluctuate on a temporal basis, it is important to understand the mechanisms mediating such changes. It is known that early memory‐dependent experiences in young animals result in hippocampal enlargement and in increased neurogenesis, including cell proliferation and neuron survival. It is less clear, however, whether temporal changes in spatial memory are also associated with changes in hippocampal anatomy and cell proliferation in fully grown and experienced adult animals. In a previous study, we experimentally demonstrated that socially subordinate mountain chickadees (Poecile gambeli) showed inferior spatial memory performance compared to their dominant group mates, in the absence of significant differences in baseline corticosterone levels. Here we investigated whether these differences in memory between dominant and subordinate birds were associated with changes in the hippocampus. Following memory tests, chickadees were injected with 5‐bromo‐2′‐deoxyuridine to label dividing cells and sacrificed 2 days after the injections. We found no significant differences in volume or the total number of neurons in the hippocampal formation between dominant and subordinate chickadees, but subordinate birds had significantly lower cell proliferation rates in the ventricular zone adjacent to both the hippocampus and mesopallium compared to the dominants. Individuals, which performed better on spatial memory tests tended to have higher levels of cell proliferation. These results suggest that social status can affect cell proliferation rates in the ventricular zone and support the hypothesis that neurogenesis might be involved in memory function in adult animals. © 2004 Wiley Periodicals, Inc. J Neurobiol, 2005