Batueva I V
Laboratory of Nerve Cell Physiology, Sechenov Institute, USSR Academy of Sciences, Leningrad.
Exp Brain Res. 1987;69(1):131-9. doi: 10.1007/BF00247036.
Synaptic responses in motoneurons in the isolated spinal cord of the lamprey during stimulation of the reticulospinal axons were examined. Chemical transmission in the synapses was partially or completely blocked by temperature reduction of the perfusing solution, pentobarbitone application or substitution of Mn2+ ions for Ca2+ in the perfusate. Excitatory postsynaptic potentials (EPSPs) which were indifferent to the influences mentioned above, had an amplitude of 6-12 mV and were capable of evoking action potentials (APs) in motoneurons due to their high amplitude, the absence of a shunting effect at the postsynaptic membrane and the fast rise-time of the wave front. The suggestion is made that the electrical transmission is involved in functioning of the lamprey nervous system. Its stability and efficiency are likely to ensure functional connection between the brain and spinal cord under such unfavourable conditions when the chemical transmission does not operate and when the ability for locomotion would be prerequisite for the individual to survive.
在刺激七鳃鳗离体脊髓中的网状脊髓轴突时，对运动神经元的突触反应进行了检查。灌注溶液温度降低、应用戊巴比妥或在灌注液中用Mn2+离子替代Ca2+可部分或完全阻断突触中的化学传递。对上述影响无反应的兴奋性突触后电位（EPSP），其幅度为6 - 12 mV，由于其幅度高、在突触后膜不存在分流效应且波前上升时间快，能够在运动神经元中引发动作电位（AP）。有人提出电传递参与七鳃鳗神经系统的功能。当化学传递不起作用且运动能力是个体生存的先决条件时，在这种不利条件下，电传递的稳定性和效率可能确保大脑与脊髓之间的功能连接。
