Costlow M E, McGuire W L
J Endocrinol. 1977 Nov;75(2):221-6. doi: 10.1677/joe.0.0750221.
The binding of 125I-labelled prolactin to normal rat tissues was examined with autoradiographic techniques. Tissue slices were incubated with 125I-labelled ovine prolactin in the presence or absence of excess unlabelled hormone to distinguish between the specific and the non-specific localization of grains. Specific binding was found in the liver, adrenal gland and kidney from female rats, and in the mammary gland, ovary, testis and prostate gland. Conversely, fat, muscle, heart, lung, and spleen from female rats and uterine tissue did not bind 125I-labelled prolactin appreciably, or show competition for binding in the presence of unlabelled hormone. In the testis, prolactin bound exclusively to Leydig cells; in the prostate gland, binding was localized in the secretory epithelium. Kidney tubules in the cortex displayed specific prolactin localization whereas the medulla did not bind prolactin. Adrenal medulla showed no hormone binding; however, the zona reticularis and to a lesser extent the zona fasciculata bound prolactin. In the ovary, grains were limited to the theca and to a lesser extent the corpus luteum and follicles. In all cases, binding was essentially abolished when unlabelled prolactin was included in the incubation medium. These results confirm reports of the presence of prolactin receptors in these tissues and serve to identify the cells within a particular organ that respond to prolactin.
采用放射自显影技术检测了¹²⁵I标记的催乳素与正常大鼠组织的结合情况。将组织切片与¹²⁵I标记的绵羊催乳素一起孵育，同时存在或不存在过量未标记的激素，以区分颗粒的特异性和非特异性定位。在雌性大鼠的肝脏、肾上腺和肾脏以及乳腺、卵巢、睾丸和前列腺中发现了特异性结合。相反，雌性大鼠的脂肪、肌肉、心脏、肺和脾脏以及子宫组织并未明显结合¹²⁵I标记的催乳素，也未在未标记激素存在时显示出结合竞争。在睾丸中，催乳素仅与睾丸间质细胞结合；在前列腺中，结合定位于分泌上皮。皮质中的肾小管显示出特异性催乳素定位，而髓质不结合催乳素。肾上腺髓质未显示激素结合；然而，网状带以及较小程度的束状带结合催乳素。在卵巢中，颗粒仅限于卵泡膜，在较小程度上也存在于黄体和卵泡中。在所有情况下，当孵育培养基中包含未标记的催乳素时，结合基本被消除。这些结果证实了这些组织中存在催乳素受体的报道，并有助于确定特定器官内对催乳素产生反应的细胞。
