Zhang Rong, Tachibana Tetsuya, Takagi Tomo, Koutoku Tomoyuki, Denbow D Michael, Furuse Mitsuhiro
Laboratory of Advanced Animal and Marine Bioresources, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka 812-8581, Japan.
Behav Brain Res. 2004 May 5;151(1-2):47-52. doi: 10.1016/j.bbr.2003.08.005.
Glucagon-like peptide-1 (GLP-1) decreased corticotropin-releasing factor (CRF)-induced behaviors in neonatal chicks, and serotonin is one of the possible mechanisms through which GLP-1 affects CRF-induced behaviors. The present experiments were conducted to confirm the effect of serotonin on CRF-induced behaviors. In Experiment 1, chicks were intracerebroventricularly injected with either saline, 0.1 microg of CRF, 5.0 microg of serotonin, or 0.1 microg of CRF plus 5.0 microg of serotonin. Injection of CRF caused excitation as evidenced by increased spontaneous activities and distress vocalizations (DVs) compared to the control group. The effect of CRF was attenuated by serotonin since chicks became quiet after given CRF with serotonin. Sleep-like behaviors were observed in the serotonin group. The number of defecations was increased by CRF and decreased by serotonin. Both CRF and serotonin increased plasma corticosterone, and the effect was synergistic. Serotonin dose-dependently decreased locomotor activities of chicks after central administration of 0.1 microg of CRF, 0.1 microg of CRF plus 2.5, 5.0, or 10.0 microg of serotonin in Experiment 2. CRF-induced DVs were modified by serotonin. Instead of DVs, tender and low-pitched vocalizations were observed in chicks treated with CRF plus serotonin, the voice frequencies of which were less than 10 kHz. In conclusion, serotonin attenuated the CRF-induced behaviors while stimulating corticosterone release. These results indicate that the role of serotonin is dependent on the behaviors being measured.
胰高血糖素样肽-1（GLP-1）可减少新生雏鸡中促肾上腺皮质激素释放因子（CRF）诱导的行为，而血清素是GLP-1影响CRF诱导行为的可能机制之一。本实验旨在证实血清素对CRF诱导行为的影响。在实验1中，给雏鸡脑室内注射生理盐水、0.1微克CRF、5.0微克血清素或0.1微克CRF加5.0微克血清素。与对照组相比，注射CRF导致兴奋，表现为自发活动增加和痛苦叫声（DVs）增多。血清素减弱了CRF的作用，因为给予CRF和血清素后雏鸡变得安静。血清素组观察到类似睡眠的行为。CRF使排便次数增加，血清素则使其减少。CRF和血清素均使血浆皮质酮增加，且作用具有协同性。在实验2中，中枢给予0.1微克CRF、0.1微克CRF加2.5、5.0或10.0微克血清素后，血清素剂量依赖性地降低了雏鸡的运动活动。血清素改变了CRF诱导的DVs。在用CRF加血清素处理的雏鸡中，未观察到DVs，而是观察到柔和且音调较低的叫声，其声音频率低于10千赫兹。总之，血清素在刺激皮质酮释放的同时减弱了CRF诱导的行为。这些结果表明血清素的作用取决于所测量的行为。
