Adejuwon C A
Afr J Med Med Sci. 1986 Mar-Jun;15(1-2):29-33.
We recently demonstrated that a substantial proportion of the previously reported widespread distribution of human chorionic gonadotropin-like material in nonplacental normal human tissues is due to non-specific activity of tissue proteases (Adejuwon & Segal, 1984). The study was extended to another polypetide hormone, measured by the same general method of radioimmunoassay. Normal tissue samples of colon (n = 1) and testes (n = 5) obtained at surgery were analysed by a highly specific and sensitive radioimmunoassay (RIA) for human prolactin (hPRL). All tissues investigated appeared to contain immunoreactive hPRL-like material (6.7 +/- 5.3 ng/g weight, mean +/- s.d.) Heat at 55 degrees C for 15-20 min was found to have no effect on the immunoreactivity of purified hPRL. Exposure of normal tissues to these conditions was, however, found to completely eliminate the hPRL-like immunoreactivity. The factor present in these normal tissues giving positive radioimmunoassay results for hPRL is not identical to native hPRL. It may be due to tissue proteases interfering with the radioligand assay. True polypeptide hormone immunoreactivity must be distinguished from proteolytic activity by treatment with heat or protease inhibitor.
我们最近证明，先前报道的人绒毛膜促性腺激素样物质在非胎盘正常人体组织中的广泛分布，很大一部分是由于组织蛋白酶的非特异性活性所致（阿德朱翁和西格尔，1984年）。该研究扩展到另一种多肽激素，采用相同的放射免疫测定通用方法进行测量。通过高度特异性和灵敏的放射免疫分析法（RIA）对手术中获取的结肠（n = 1）和睾丸（n = 5）的正常组织样本进行人催乳素（hPRL）分析。所有研究的组织似乎都含有免疫反应性hPRL样物质（6.7±5.3纳克/克重量，平均值±标准差）。发现55摄氏度加热15 - 20分钟对纯化的hPRL的免疫反应性没有影响。然而，发现正常组织在这些条件下处理后会完全消除hPRL样免疫反应性。这些正常组织中对hPRL放射免疫测定呈阳性结果的因子与天然hPRL不同。这可能是由于组织蛋白酶干扰了放射配体测定。必须通过加热或蛋白酶抑制剂处理将真正的多肽激素免疫反应性与蛋白水解活性区分开来。
