Thiocyanate stabilizes AMPA binding to the quisqualate receptor.
Thiocyanate stabilizes AMPA binding to the quisqualate receptor.
复制标题
硫氰酸盐可稳定 AMPA 与使君子酸受体的结合。
DOI：
10.1016/0014-2999(88)90383-4
复制
发表时间：
1988
影响因子：
5
通讯作者：
Young,AB
中科院分区：
文献类型：
--
作者：
Nielsen,EO;Cha,JH;Honoré,T;Penney,JB;Young,AB
钙离子和氯离子刺激[3 H]谷氨酸结合到使君子酸敏感的[3 H]谷氨酸结合位点4倍，通过定量放射自显影测量，而100 mM硫氰酸钾没有额外的效果。相反，钙和氯对[3 H]（RS）-α-氨基-3-羟基-5-甲基异恶唑-4-丙酸（[3 H]AMPA）的结合几乎没有影响，但100 mM硫氰酸盐刺激结合4倍。在没有硫氰酸盐的情况下，AMPA从小脑分子层中的使君子酸敏感结合位点置换很少的[3 H]谷氨酸结合。然而，在硫氰酸盐的存在下，AMPA成为一个更有效的置换剂，但仍然只置换了44%的使君子酸敏感的[3 H]谷氨酸结合。[~ 3 H]谷氨酸结合到使君子酸敏感位点的分布与[~ 3 H]AMPA结合的分布相似但不相同。而AMPA可置换的[3 H]谷氨酸结合的分布与[3 H]AMPA结合的分布高度相关（r = 0.97，P<0.0005）。结果表明，AMPA结合到使君子酸敏感的[3 H]谷氨酸盐结合位点的一个亚类，其高度受离子环境的影响，并且使君子酸敏感的结合位点以几种状态存在。
Calcium and chloride ions stimulated [3H]glutamate binding to quisqualate-sensitive [3H]glutamate binding sites 4-fold, as measured by quantitative autoradiography, whereas 100 mM potassium thiocyanate had no additional effect. In contrast, calcium and chloride had little effect on the binding of [3H](RS)-α-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid ([3H]AMPA), but 100 mM thiocyanate stimulated binding 4-fold. AMPA displace little [3H]glutamate binding from quisqualate-sensitive binding sites in the molecular layer of the cerebellum in the absence of thiocyanate. However, in the presence of thiocyanate AMPA became a more effective displacer, but still displaced only 44% of the quisqualate-sensitive [3H]glutamate binding. The distribution of [3H]glutamate binding to quisqualate-sensitive sites was similar to but not identical with that of [3H]AMPA binding. However, the distribution of AMPA-displaceable [3H]glutamate binding correlated highly (r = 0.97, P<0.0005) with that of [3H]AMPA binding. The results suggest that AMPA binds to a subclass of quisqualate-sensitive [3H]glutamate binding sites that are highly influenced by ionic environment and that quisqualate-sensitive binding sites exist in several states.