Velumian A A
Zh Evol Biokhim Fiziol. 1977 May-Jun;13(3):407-9.
Intracellular recordings were made from lumbar motoneurones of the isolated spinal cord of the frog while glutamate, GABA or glycine were applied iontophoretically through the extracellular microelectrode. Glutamate had depolarizing excitatory effects and caused slight (if any) increase in membrane conductance. Responses to BABA and glycine were inhibitory regardless of the sign of membrane potential shift as revealed by conductance measurements and the dependence of anti- and orthodromically induced potentials on their application. Blocade of synaptic transmission by reducing extracellular Ca++ and increasing Mg++ concentrations did not alter the effects of application indicating the immediate activation of the postsynaptic membrane. These results are in agreement with the possible role of GABA and glycine as transmitters in inhibitory as transmitters in inhibitory synapses. The function of glutamate remains uncertain.
在青蛙离体脊髓的腰运动神经元上进行细胞内记录，同时通过细胞外微电极以离子电泳方式施加谷氨酸、γ-氨基丁酸（GABA）或甘氨酸。谷氨酸具有去极化兴奋作用，并使膜电导略有增加（若有增加的话）。对GABA和甘氨酸的反应是抑制性的，这与通过电导测量所揭示的膜电位变化的符号以及逆行和顺行诱发电位对其施加的依赖性无关。通过降低细胞外钙离子浓度和增加镁离子浓度来阻断突触传递，并不会改变施加药物的效果，这表明突触后膜被直接激活。这些结果与GABA和甘氨酸作为抑制性突触中的递质的可能作用相一致。谷氨酸的功能仍不确定。
