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用放射性配体受体结合实验研究了人大脑皮层膜与［３￣Ｈ］ＤＬ－谷氨酸结合的特性。人大脑皮层与谷氨酸特异性结合的最适条件是在４℃，ＨＥＰＥＳ缓冲液（ｐＨ６．４－８．６）中孵温３０－４０ｍｉｎ。结合实验前洗涤膜样品至为重要。人大脑皮层膜与谷氨酸特异性结合是可饱和的，其ＫＤ和Ｂｍａｘ值分别为１０３和１．６７ｎｍｏｌ·Ｌ－１蛋白，Ｈｉｌｌ系数１．０６．谷氨酸受体激动剂对人大脑皮层膜与谷氨酸结合的抑制强度依次为Ｌ－谷氨酸＞ＤＬ－谷氨酸＞红藻氨酸＞Ｎ－甲基－Ｄ－天冬氨酸（ＮＭＤＡ）＞Ｄ－谷氨酸。谷氨酸受体亚型拮抗剂２－氨基－５－磷酸基戊酸和６，７－二硝基唑喔啉－２，３－二酮（１ｎｍｏｌ·Ｌ－１）分别取代了５４％和５６％的特异性谷氨酸结合。１．２５ｎｍｏｌ·Ｌ－１镁离子抑制了５５％的特异性谷氨酸结合。人大脑皮层膜与谷氨酸的特异性结合不依赖钠离子，部分依赖于钙离子。人大脑皮层膜与谷氨酸特异性结合至少涉及到ＮＭＤＡ和红藻氨酸两个谷氨酸受体亚型。
Radioligand binding experiments were performed to investigate the binding properties of human cortical membranes to [3-H] DL-glutamic acid. The optimal conditions for the specific binding of human cerebral cortex to glutamate are incubation in HEPES buffer (pH 6.4-8.6) for 30-40 min at 4 ° C. It is important to combine the membrane samples before the experiment. The specific binding of human cerebral cortex membrane with glutamate is saturable, with KD and Bmax values of 103 and 1.67 nmol·L-1, respectively. The Hill coefficient is 1.06. The inhibitory effect of glutamate receptor agonist on the binding of human cerebral cortex membrane to glutamate was L-glutamic acid> DL-glutamic acid> kainic acid> N-methyl-D-aspartic acid (NMDA)> D-glutamic acid. The glutamate receptor subtype antagonists 2-amino-5-phosphate pentanoic acid and 6,7-dinitro oxazol-2,3-dione (1 nmol·L -1) replaced 54% and 56% of specific glutamate binding. 1.25 nmol·L-1 magnesium ions inhibited 55% of the specific glutamate binding. The specific binding of human cerebral cortex membrane to glutamate does not depend on sodium ions and is partly dependent on calcium ions. Specific binding of human cerebral cortex membrane to glutamate involves at least two glutamate receptor subtypes of NMDA and kainic acid.