论文部分内容阅读
本文的研究目的旨在鉴定突触质膜上的糖皮质激素特异膜结合位点（ＧＣＭＢ），并研究其配体结台特性和理化性质。放射配体结合分析表明，［３Ｈ］皮质酮能与ＧＣＭＢ作饱和结合，呈正协同方式。其最大结合容量（Ｒ０）为４６．６７±４．６２ｆｍｏｌ／Ｌ，平衡解离常数（Ｋｄ）为９７．４８±１８．８５ｎｍｏｌ／Ｌ，Ｈｉｌｌ系数为１．６３３±０．０８２。不同甾体与ＧＣＭＢ的亲和力依次为：ＲＵ２６７５２，醛固酮＞皮质酮，皮质醇＞ＲＵ２６９８８，孕酮，Ｒ５０２０，去炎松缩酮＞睾酮，雌二醇＞ＲＵ３８４８６＞地塞米松。ＧＣＭＢ具有温度稳定性，并可被去垢剂ＴｒｉｔｏｎＸ—１００溶脱，被胰蛋白酶水解，易受巯基乙醇影响。二价阳离子（Ｃａ２＋、Ｍｇ２＋）有助于ＧＢＭＢ与配体结合。我们的实验结果强烈提示：ＧＢＭＢ满足作为受体的基本判据是一个与胞内糖皮质激素不相同的新型糖皮质激素受体，或肾上腺皮质激素受体。
The purpose of this study was to identify glucocorticoid-specific membrane-associated sites (GCMB) on the synaptic plasma membrane and to investigate its ligand-binding properties and physico-chemical properties. Radioligand binding analysis showed that [3H] corticosterone could be combined with GCMB in a positive manner. The maximum binding capacity (R0) was 46.67 ± 4.62 fmol / L, the equilibrium dissociation constant (Kd) was 97.48 ± 18.85 nmol / L, and the Hill coefficient was 1.633 ± 0.082. The affinity of different steroids to GCMB was as follows: RU26752, aldosterone> corticosterone, cortisol> RU26988, progesterone, R5020, triamcinolone acetonide> testosterone, estradiol> RU38486> dexamethasone. GCMB is temperature-stable and is soluble in the detergent Triton X-100, hydrolyzed by trypsin and susceptible to mercaptoethanol. Divalent cations (Ca2 +, Mg2 +) contribute to the binding of GBMB to ligands. Our results strongly suggest that the basic criterion for GBMB satisfaction as a receptor is a novel glucocorticoid receptor, or adrenocorticotropic hormone receptor, that is different from intracellular glucocorticoid.