Shapovalov A I
Zh Evol Biokhim Fiziol. 1979 May-Jun;15(3):268-77.
Investigation of the mechanisms of junctional transmission in the isolated spinal cord in cyclostomes, amphibians, reptilia and mammals reveals the decrease in the number of electrical synapses during evolution from primitive to more advanced vertebrates. Electrical transmission is lacking in reptilian and mammalian cord. On the basis of these data, the analysis of the unitary EPSPs evoked in motoneurons of the lamprey and frog by intracellular stimulation of reticulospinal axons and primary afferent fibers and dendrodendritic interaction between motoneurons, a hypothesis is advanced that neurons of similar type may communicate through pure electrical junctions, whereas successive synaptic articulations between different functional groups of neurons are formed by mixed or chemical synapses. The cellular mechanisms controlling interneuronal communications are discussed.
对圆口纲动物、两栖动物、爬行动物和哺乳动物的离体脊髓中突触传递机制的研究表明，从原始脊椎动物到更高级脊椎动物的进化过程中，电突触数量减少。爬行动物和哺乳动物的脊髓中不存在电传递。基于这些数据，通过对七鳃鳗和青蛙运动神经元进行细胞内刺激网状脊髓轴突和初级传入纤维所诱发的单位兴奋性突触后电位（EPSP）以及运动神经元之间的树突-树突相互作用进行分析，提出了一个假说：相似类型的神经元可能通过纯电突触进行通信，而不同功能组神经元之间连续的突触连接则由混合或化学突触形成。文中还讨论了控制神经元间通信的细胞机制。
