Thiriet G, Kempf E, Ebel A
Centre de Neurochimie, Strasbourg, France.
Brain Res Dev Brain Res. 1994 Mar 18;78(1):102-8. doi: 10.1016/0165-3806(94)90014-0.
Our previous analyses of the functional maturation of cholinergic neurotransmission in the chick embryo spinal cord showed that 12 days of development represents a crucial stage in the maturation of cholinergic neurotransmission. Since supraspinal inputs are essential for the modulation of motoneuron activity in the embryo, we studied, using a pharmacological approach, the regulatory effects of biogenic amines on the developing cholinergic neurotransmission. We show that, in spite of the early occurrence of serotonin and norepinephrine in the developing spinal cord, the modulatory influences of these biogenic amines on motoneurons can only be effective from 12 days of incubation onwards. It also appears that the inputs of biogenic amines on cholinergic activity is a sequential event. Whereas serotonin (5-HT) begins to stimulate cholinergic activity from 12 days of incubation, norepinephrine inputs are only observed at later stages (17 days of development). These observations underline the specific turning point in the functional maturation of motoneurons, we noted in our previous studies. At the end of embryonic life a specific interrelationship between the biogenic amines was noted, its effect on the cholinergic system may lead to a more precise motor control, preparing the chick embryo for hatching.
我们之前对鸡胚脊髓中胆碱能神经传递功能成熟的分析表明，发育12天是胆碱能神经传递成熟的关键阶段。由于脊髓上输入对于胚胎中运动神经元活动的调节至关重要，我们采用药理学方法研究了生物胺对发育中的胆碱能神经传递的调节作用。我们发现，尽管血清素和去甲肾上腺素在发育中的脊髓中出现得较早，但这些生物胺对运动神经元的调节作用仅在孵化12天后才有效。生物胺对胆碱能活性的输入似乎也是一个有序的过程。血清素（5-HT）从孵化12天开始刺激胆碱能活性，而去甲肾上腺素的输入仅在后期（发育17天）才观察到。这些观察结果强调了我们在之前研究中注意到的运动神经元功能成熟的特定转折点。在胚胎发育末期，发现生物胺之间存在特定的相互关系，其对胆碱能系统的作用可能导致更精确的运动控制，为鸡胚孵化做好准备。
