Laboratory of Neuropharmacology, Institute of Medical Biochemistry, First Faculty of Medicine, Charles University in Prague, Albertov 4, 128 00 Prague 2, Czech Republic.
Neurosci Lett. 2011 Sep 20;502(3):147-51. doi: 10.1016/j.neulet.2011.06.051. Epub 2011 Jul 3.
The neuropeptide galanin has been recognized as a possible neurotransmitter/neuromodulator, and in addition has been implicated in anxiety- and depression-related behaviors. The present study demonstrates increased locomotion and rearing after galanin (0.3mg/kg) that was given intraperitoneally (i.p.) to intact Wistar rats which were tested 1h later in the open field (OF). These effects, which suggest an anxiolytic-like action, were blocked by i.p. administered peptidic galanin antagonist M40. Further, the locomotion increase caused by galanin and the inhibitory effect of M40 persisted for 48h without additional treatment. Rats exposed to restraint stress (lasting 60min) for three consecutive days and tested 1h after stress termination exhibited reduced locomotion and exploration in the OF. Galanin (0.3 and 1.0mg/kg) given immediately after each stress exposure prevented the decrease of locomotion and exploration induced by stress in all trials. When the test was repeated 6 days later without stress and galanin treatment the reduction of locomotion produced by stress persisted; the anti-stress behavioral effects of both galanin doses were also present. Testing performed on the 12th day after the last stress and galanin treatment with 0.3mg/kg revealed an increased locomotion compared with unstressed and stress-exposed rats. Our results demonstrate that behavioral effects of the peptide galanin are evident even after i.p. administration. These results also suggest that galanin elicits stress-modulatory action, and support the notion that the galaninergic system may serve as a drug target in stress-related conditions.
神经肽甘丙肽被认为是一种可能的神经递质/神经调质，此外，它还与焦虑和抑郁相关的行为有关。本研究表明，完整的 Wistar 大鼠腹腔内（i.p.）给予甘丙肽（0.3mg/kg）后，1 小时后在开阔场（OF）中表现出增加的运动和竖起。这些作用表明具有抗焦虑样作用，被腹腔内给予的肽甘丙肽拮抗剂 M40 阻断。此外，甘丙肽引起的运动增加和 M40 的抑制作用持续 48 小时而无需额外治疗。连续 3 天暴露于束缚应激（持续 60min）并在应激结束后 1 小时测试的大鼠在 OF 中表现出运动和探索减少。在每次应激暴露后立即给予甘丙肽（0.3 和 1.0mg/kg）可防止应激引起的运动和探索减少。当在没有应激和甘丙肽治疗的情况下 6 天后重复测试时，应激引起的运动减少仍然存在；两种甘丙肽剂量的抗应激行为作用也存在。在最后一次应激和甘丙肽治疗后第 12 天用 0.3mg/kg 进行测试时，与未受应激和应激暴露的大鼠相比，运动增加。我们的结果表明，即使在腹腔内给药后，肽甘丙肽的行为作用也很明显。这些结果还表明，甘丙肽引起应激调节作用，并支持甘丙肽能系统可能作为应激相关疾病的药物靶点的观点。
