Sawada S, Yamamoto C
Exp Brain Res. 1985;59(2):226-31. doi: 10.1007/BF00230901.
The actions of pentobarbital sodium (Pent) on receptors for glutamate (Glu) and related compounds were studied in thin sections of the guinea pig hippocampus. Depolarizations induced by Glu and quisqualate (Quis) in CA3 neurons were reduced in amplitude during iontophoretic administration of Pent. This action of Pent was not accompanied by any noticeable changes in membrane potential or neuron input resistance. Depolarizations induced by N-methyl-D-aspartate were less sensitive to Pent. The fast kainate (KA) response was as susceptible as the Glu response, whereas the slow KA response was unaffected by Pent in three quarters of the neurons examined. Pent suppressed the Glu response at lower concentrations than required to potentiate responses to gamma-amino butyric acid. Excitatory postsynaptic potentials (EPSPs) elicited by stimulation of mossy fibers were suppressed by Pent. The EPSPs were a little more resistant to Pent than were the Glu responses. These results indicate that Pent blocks receptors for excitatory amino acids in the hippocampus. Of the three different populations of the receptors, Quis receptors are the most sensitive to Pent and KA receptors are the least sensitive. The suppression of the EPSPs is in accordance with the notion that Glu is the transmitter released from mossy fibers.
在豚鼠海马体薄片中研究了戊巴比妥钠（Pent）对谷氨酸（Glu）及相关化合物受体的作用。在离子电渗法给予Pent期间，CA3神经元中由Glu和quisqualate（Quis）诱导的去极化幅度降低。Pent的这种作用并未伴随着膜电位或神经元输入电阻的任何明显变化。由N - 甲基 - D - 天冬氨酸诱导的去极化对Pent不太敏感。快速海人酸（KA）反应与Glu反应一样敏感，而在四分之三的检测神经元中，缓慢的KA反应不受Pent影响。Pent在比增强对γ-氨基丁酸反应所需浓度更低时就抑制了Glu反应。刺激苔藓纤维引发的兴奋性突触后电位（EPSP）被Pent抑制。EPSP对Pent的抗性比Glu反应略强。这些结果表明Pent阻断海马体中兴奋性氨基酸的受体。在三种不同类型的受体中，Quis受体对Pent最敏感，而KA受体最不敏感。EPSP的抑制与Glu是从苔藓纤维释放的递质这一观点相符。
