Tsukada Y, Kanamatsu T, Takahara H
Institute of Life Science, Soka University, Tokyo, Japan.
Neurochem Res. 1999 Feb;24(2):315-20. doi: 10.1023/a:1022582625602.
The imprinting behavior of chicks was quantified as a preference score (correct response ratio) achieved in a running wheel apparatus. A total of 249 chicks were exposed to an imprinting stimulus and tested for stimulus-approaching behavior. The chicks were then classified as good learners (imprinted), poor learners (non-imprinted) and a gray-zone group, those were 46%, 31% and 23% of the total chicks respectively. Using the classified chicks, the acetylcholine (ACh) and glutamate releases from the medial hyperstriatum ventrale (MHV) of the chick forebrains were determined by in vivo microdialysis. The non-imprinted chicks were used as yoked controls. Increases of ACh and glutamate released were observed in the imprinted chicks during exposure to the imprinting stimulus, whereas there were no changes in the release of these neurotransmitters in the non-imprinted chicks during the imprinting exposure. These results might be indicated that cholinergic and glutamatergic synapses which are newly formed as functioning synapses with imprinting stimulus in the MHV are involved in the performance of imprinting behavior.
雏鸡的印记行为通过在转轮装置中获得的偏好分数（正确反应比率）进行量化。总共249只雏鸡接受印记刺激并测试其接近刺激的行为。然后将雏鸡分为学习能力强的（印记的）、学习能力差的（未印记的）和一个灰色区域组，它们分别占雏鸡总数的46%、31%和23%。使用分类后的雏鸡，通过体内微透析测定雏鸡前脑内侧上纹状体腹侧（MHV）中乙酰胆碱（ACh）和谷氨酸的释放。未印记的雏鸡用作配对对照。在印记雏鸡暴露于印记刺激期间，观察到ACh和谷氨酸的释放增加，而在印记暴露期间，未印记雏鸡中这些神经递质的释放没有变化。这些结果可能表明，在MHV中作为与印记刺激形成功能突触而新形成的胆碱能和谷氨酸能突触参与了印记行为的表现。
