Dalezios Y, Matsokis N
Department of Biology, University of Patras, Greece.
Neurochem Res. 1993 Mar;18(3):305-11. doi: 10.1007/BF00969087.
The biochemical and pharmacological properties of nuclear [3H]flunitrazepam in brain tissues were studied. Nuclear [3H]flunitrazepam binding is saturable for both central and peripheral binding sites. Inosine and hypoxanthine displace nuclear [3H]flunitrazepam binding with greater potency than the membrane [3H]flunitrazepam binding. Triiodothyronine (T3) increases the maximum number of binding sites (Bmax) of nuclear [3H]flunitrazepam binding in vitro while thyroxine (T4) does not have any effect. Diazepam reduces the affinity of nuclear 125I-T3 binding in vitro, while the Bmax is not affected significantly. Mild digestion of chromatin, using micrococcal nuclease, reveals that a major portion of nuclear [3H]flunitrazepam binding sites are located on chromatin. These data suggest a functional role for nuclear benzodiazepine binding and a possible modulatory effect of benzodiazepines on T3 binding with its nuclear receptors.
研究了脑组织中核[³H]氟硝西泮的生化和药理特性。核[³H]氟硝西泮结合对中枢和外周结合位点均具有饱和性。肌苷和次黄嘌呤取代核[³H]氟硝西泮结合的效力高于膜[³H]氟硝西泮结合。三碘甲状腺原氨酸（T3）在体外增加核[³H]氟硝西泮结合的最大结合位点数（Bmax），而甲状腺素（T4）则无任何影响。地西泮在体外降低核¹²⁵I-T3结合的亲和力，而Bmax未受到显著影响。使用微球菌核酸酶对染色质进行轻度消化显示，核[³H]氟硝西泮结合位点的主要部分位于染色质上。这些数据表明核苯二氮䓬结合具有功能作用，且苯二氮䓬可能对T3与其核受体的结合具有调节作用。
