Danzo B J, Dunn J C, Davies J
Mol Cell Endocrinol. 1982 Nov-Dec;28(3):513-27. doi: 10.1016/0303-7207(82)90143-5.
Androgen-binding protein (ABP) is present in the guinea-pig testis, epididymis and epididymal fluid. Guinea-pig ABP sediments as an approx. 4.6S species on sucrose gradients containing 0.01 M KCl. Electrophoresis on non-denaturing polyacrylamide gels indicated that specific androgen binding was present in epididymal cytosol, but not in plasma. Time-course studies indicated that binding equilibrium is approached in about 2.5 h; the dissociation half-time of [3H]5 alpha-DHT from guinea-pig ABP is 5.64 +/- 0.62 h (n = 6) at 4 degrees C. The relative affinities of some steroids for guinea-pig ABP in relation to 5 alpha-DHT = 1 are: testosterone = 0.55 +/- 0.13 (n = 4), estradiol = 0.14 +/- 0.03 (n = 4), the anti-androgen cyproterone acetate = 0.0025 +/- 0.0002 (n = 3). Guinea-pig ABP exhibited an equilibrium dissociation constant of 6.34 +/- 0.52 nM (n = 3) at 4 degrees C and there were 3.43 +/- 0.78 (n = 3) pmoles of binding sites per mg of protein when homogenates of the whole epididymis were assayed. The concentration of ABP was lowest in the caput-corpus region of the epididymis, highest in the proximal cauda, and intermediate in the distal cauda. Essentially all of the ABP present in the distal cauda was intraluminal, as evidenced by the fact that flushing of the duct eliminated most of the [3H]5 alpha-DHT binding activity.
雄激素结合蛋白（ABP）存在于豚鼠的睾丸、附睾及附睾液中。豚鼠ABP在含0.01M KCl的蔗糖梯度中沉降为约4.6S的组分。在非变性聚丙烯酰胺凝胶上进行电泳表明，附睾胞质溶胶中存在特异性雄激素结合，但血浆中不存在。时间进程研究表明，约2.5小时可达到结合平衡；在4℃时，[3H]5α -双氢睾酮从豚鼠ABP上解离的半衰期为5.64±0.62小时（n = 6）。一些类固醇与豚鼠ABP的相对亲和力（相对于5α -双氢睾酮 = 1）为：睾酮 = 0.55±0.13（n = 4），雌二醇 = 0.14±0.03（n = 4），抗雄激素醋酸环丙孕酮 = 0.0025±0.0002（n = 3）。豚鼠ABP在4℃时的平衡解离常数为6.34±0.52 nM（n = 3），当对整个附睾匀浆进行检测时，每毫克蛋白质有3.43±0.78（n = 3）皮摩尔的结合位点。附睾头 - 体区域的ABP浓度最低，近侧附睾尾最高，远侧附睾尾居中。远侧附睾尾中基本上所有的ABP都在管腔内，这一点可通过冲洗管道消除大部分[3H]5α -双氢睾酮结合活性得到证明。
