Shen Pei, Yue Qiang, Fu Wan, Tian Shao-Wen, You Yong
Department of Neurology, The First Affiliated Hospital, University of South China, Hengyang, Hunan, 421001, PR China.
Department of Physiology, Hengyang Medical College, University of South China, Hengyang, Hunan, 421001, PR China.
Neurosci Lett. 2019 Mar 23;696:151-155. doi: 10.1016/j.neulet.2018.11.051. Epub 2018 Nov 27.
A large number of studies have demonstrated that the hippocampus has important influences on stress response and memory. The abundant expressions of apelin and its receptor APJ in the hippocampus may imply potential involvement of apelin/APJ signaling in modulating stress-related memory performance deficit. In our previous study, apelin-13 ameliorates memory performance deficit in acute stressed rats. Here, we further examined whether apelin-13 can ameliorate memory performance deficit in chronic stressed rats. Rats were exposed to chronic water-immersion restraint stress (CWIRS) for 4 weeks. After stress withdrawal, apelin-13 was intracerebroventricularly infused once a day for one week. The novel object recognition test (NORT) and Y-maze test (YMT), two hippocampus-dependent memory tasks, were performed to assess memory performance. We found that apelin-13 restored CWIRS-induced decline in the discrimination index and alternation ratio in NORT and YMT, respectively. Furthermore, apelin-13 ameliorated CWIRS-induced hippocampal BDNF expression deficit, and the TrkB receptor antagonist ANA-12 blocked the ameliorative effect of apelin-13 on memory performance deficit in CWIRS rats. The current observations indicate that apelin-13 ameliorates CWIRS-induced memory performance deficit through upregulation of BDNF in rats.
大量研究表明，海马体对应激反应和记忆有重要影响。海马体中apelin及其受体APJ的丰富表达可能意味着apelin/APJ信号通路可能参与调节与应激相关的记忆表现缺陷。在我们之前的研究中，apelin-13可改善急性应激大鼠的记忆表现缺陷。在此，我们进一步研究apelin-13是否能改善慢性应激大鼠的记忆表现缺陷。将大鼠暴露于慢性水浸束缚应激（CWIRS）4周。应激撤除后，每天一次脑室内注射apelin-13，持续一周。采用新颖物体识别测试（NORT）和Y迷宫测试（YMT）这两项依赖海马体的记忆任务来评估记忆表现。我们发现，apelin-13分别恢复了CWIRS诱导的NORT和YMT中辨别指数和交替率的下降。此外，apelin-13改善了CWIRS诱导的海马体脑源性神经营养因子（BDNF）表达缺陷，并且TrkB受体拮抗剂ANA-12阻断了apelin-13对CWIRS大鼠记忆表现缺陷的改善作用。目前的观察结果表明，apelin-13通过上调大鼠海马体中的BDNF来改善CWIRS诱导产生的记忆表现缺陷。
