Sato Kaito, Chiba Shuichi, Hatakeyama Taichi, Matsuwaki Takashi, Watanabe Gen, Kawaguchi Maiko
Lab of Animal Behavior and Environmental Science, Graduate School of Agriculture, Meiji University, Kawasaki, Japan.
Faculty of Veterinary Medicine, Okayama University of Science, Imabari, Japan.
Neuropsychopharmacol Rep. 2025 Mar;45(1):e12514. doi: 10.1002/npr2.12514.
Pituitary adenylate cyclase-activating polypeptide (PACAP) affects rodents' stress-related behaviors, such as anxiety-like behavior or fear conditioning. However, previous studies have investigated the effect of intracerebroventricular, but not hippocampal, injection of this PAC1R-selective antagonist (PACAP-6-38) on anxiety-like behavior. However, it has been reported that administration of PACAP-6-38 to the dorsal hippocampus reduces the fear response in a fear conditioning test. Therefore, this study aimed to determine whether the effect of dorsal hippocampal PACAP-6-38 injection in Sprague-Dawley rats can affect anxiety-like behavior assessed by an elevated plus-maze test. As a result, rats treated with PACAP-6-38 spent longer time in open arms than those with saline, suggesting that this drug has an anxiolytic effect. In conclusion, the role of PACAP in the dorsal hippocampus can promote anxiety-like behavior.
垂体腺苷酸环化酶激活多肽（PACAP）会影响啮齿动物与应激相关的行为，如焦虑样行为或恐惧条件反射。然而，以往的研究调查了脑室内注射这种PAC1R选择性拮抗剂（PACAP-6-38）对焦虑样行为的影响，而非海马内注射的影响。不过，有报道称向背侧海马注射PACAP-6-38可在恐惧条件反射测试中降低恐惧反应。因此，本研究旨在确定向Sprague-Dawley大鼠背侧海马注射PACAP-6-38是否会影响通过高架十字迷宫试验评估的焦虑样行为。结果显示，接受PACAP-6-38治疗的大鼠在开放臂中停留的时间比接受生理盐水治疗的大鼠更长，这表明该药物具有抗焦虑作用。总之，PACAP在背侧海马中的作用会促进焦虑样行为。
