Yamada Y, Ujihara H, Sada H, Ban T
Department of Pharmacology, Yamaguchi University School of Medicine, Japan.
FEBS Lett. 1995 Dec 27;377(3):390-2. doi: 10.1016/0014-5793(95)01402-0.
We compared the effects of Pb2+ on four types of NMDA receptors expressed in Xenopus oocytes. Pb2+ reduced the currents evoked by glutamate and glycine. The Ki values of the receptors, epsilon 1/zeta 1, epsilon 2/zeta 1, epsilon 3/zeta 1 and epsilon 4/zeta 1, were 39, 34, 54 and 42 microM, respectively, and their Hill coefficients were 0.53, 4.6, 0.52 and 0.37, respectively. The epsilon 2/zeta 1 receptor that was inhibited in the presence of over 30 microM Pb2+ was not recovered to the control level after a Pb2+ washout for over 30 min, suggesting that epsilon 2/zeta 1 is responsible for the chronic Pb2+ intoxication in the nervous system.
我们比较了Pb2+对非洲爪蟾卵母细胞中表达的四种类型N-甲基-D-天冬氨酸（NMDA）受体的影响。Pb2+降低了由谷氨酸和甘氨酸诱发的电流。受体epsilon 1/zeta 1、epsilon 2/zeta 1、epsilon 3/zeta 1和epsilon 4/zeta 1的抑制常数（Ki值）分别为39、34、54和42微摩尔，其希尔系数分别为0.53、4.6、0.52和0.37。在超过30微摩尔Pb2+存在下被抑制的epsilon 2/zeta 1受体，在Pb2+洗脱超过30分钟后未恢复到对照水平，这表明epsilon 2/zeta 1与神经系统中慢性Pb2+中毒有关。
