Persengiev S P
Department of Immunoneuroendocrinology, Bulgarian Academy of Sciences, Sofia.
Life Sci. 1992;51(9):647-51. doi: 10.1016/0024-3205(92)90237-j.
Specific binding sites for 2-[125I] iodomelatonin, a selective radiolabeled melatonin receptor ligand, were detected and characterized in rat adrenal membranes. Saturation studies demonstrated that 2-[125I]iodomelatonin binds to a single class of sites with an affinity constant (Kd) of 541 pM and a total binding capacity (Bmax) of 3.23 fmol/mg protein. Competition experiments revealed that the relative order of potency of compounds tested was as follows: 6-chloromelatonin greater than 2-iodomelatonin greater than melatonin greater than 5-methoxytryptamine greater than 5-methoxytryptophol. The highest density of binding sites was found in membranes from nuclear (0.76 fmol/mg protein) and mitochondrial (1.82 fmol/mg protein) subcellular fractions.
在大鼠肾上腺膜中检测并鉴定了2-[¹²⁵I]碘褪黑素（一种选择性放射性标记的褪黑素受体配体）的特异性结合位点。饱和研究表明，2-[¹²⁵I]碘褪黑素与一类位点结合，其亲和常数（Kd）为541 pM，总结合容量（Bmax）为3.23 fmol/mg蛋白质。竞争实验显示，所测试化合物的效力相对顺序如下：6-氯褪黑素＞2-碘褪黑素＞褪黑素＞5-甲氧基色胺＞5-甲氧基色醇。在细胞核（0.76 fmol/mg蛋白质）和线粒体（1.82 fmol/mg蛋白质）亚细胞组分的膜中发现了最高密度的结合位点。
