Rui H, Brekke I, Torjesen P A, Purvis K
Mol Cell Endocrinol. 1986 Jun;46(1):53-7. doi: 10.1016/0303-7207(86)90069-9.
Exposure of explants of rat ventral prostates and a rat Leydig cell tumour to ovine prolactin for 20 h caused alterations of the subsequent membrane binding of 125I-human prolactin to an extent and in a direction dependent on the dose of hormone used. Low prolactin concentrations (1-10 micrograms/2 ml) were associated with an increase in binding (up-regulation) which was 75% in the case of the prostatic tissue and 500% in the case of the tumour tissue above control levels. Higher concentrations caused a dose-dependent decrease in binding to below control levels (down-regulation), alterations which could not be explained by receptor occupancy. Time studies with an up-regulatory dose of hormone (3 micrograms/2 ml) indicated that the effects of prolactin on its receptor did not begin to become manifest until after 6-12 h of culture. The results suggest that homologous up-regulation of prolactin binding may be a general feature of prolactin target organs and that explant cultures of prostatic tissue may provide a convenient model for exploring its mechanisms.
将大鼠腹侧前列腺组织块和大鼠睾丸间质细胞瘤组织块暴露于绵羊催乳素中20小时，会导致随后¹²⁵I-人催乳素的膜结合发生改变，其程度和方向取决于所用激素的剂量。低浓度催乳素（1 - 10微克/2毫升）会使结合增加（上调），前列腺组织中这种增加比对照水平高75%，肿瘤组织中则高500%。较高浓度会导致结合呈剂量依赖性下降至对照水平以下（下调），这种改变无法用受体占据情况来解释。用上调剂量的激素（3微克/2毫升）进行的时间研究表明，催乳素对其受体的作用直到培养6 - 12小时后才开始显现。结果表明，催乳素结合的同源上调可能是催乳素靶器官的一个普遍特征，并且前列腺组织块培养可能为探索其机制提供一个便利的模型。
