Jones R L, Critchley H O, Brooks J, Jabbour H N, McNeilly A S
Department of Obstetrics and Gynecology, University of Edinburgh, Scotland.
J Clin Endocrinol Metab. 1998 Jan;83(1):258-62. doi: 10.1210/jcem.83.1.4506.
Extrapituitary PRL is synthesized by the decidualized endometrial stromal cells from the mid to late secretory phase in the nonpregnant cycle and throughout pregnancy. The function of PRL in the uterus is unknown, but the temporal expression indicates a role in implantation and placentation. PRL is a powerful immunoregulatory agent, and thus, a role in modulating endometrial leukocytes may be envisaged. To investigate the site of action of PRL, immunohistochemistry was conducted to localize the PRL receptor (PRL-R). In addition, ribonucleic acid was extracted and reverse transcriptase-PCR for PRL-R was conducted. PRL-R protein was immunolocalized to the glandular epithelium and a subset of stromal cells from the mid to late secretory phase of the menstrual cycle and in early decidua. PRL-R transcripts were also detected from the late secretory phase and first trimester decidua. These findings indicate that the receptor is expressed in a temporal pattern similar to that of PRL. PRL-R expression in the glandular epithelium is consistent with a role in regulating glandular activity. Furthermore, immunoreactivity for PRL-R in a subset of stromal cells may be evidence for paracrine interactions between decidualized cells or an immunoregulatory role for PRL.
垂体外催乳素由非妊娠周期分泌中期至晚期以及整个孕期的蜕膜化子宫内膜基质细胞合成。催乳素在子宫中的功能尚不清楚，但根据其表达时间推测它在着床和胎盘形成过程中发挥作用。催乳素是一种强大的免疫调节因子，因此，可以设想它在调节子宫内膜白细胞方面发挥作用。为了研究催乳素的作用位点，进行了免疫组织化学实验以定位催乳素受体（PRL-R）。此外，提取了核糖核酸并进行了PRL-R的逆转录聚合酶链反应。PRL-R蛋白在月经周期分泌中期至晚期的腺上皮以及早期蜕膜的一部分基质细胞中被免疫定位。在分泌晚期和孕早期的蜕膜中也检测到了PRL-R转录本。这些发现表明该受体的表达模式与催乳素相似。腺上皮中PRL-R的表达与调节腺体活动的作用一致。此外，一部分基质细胞中PRL-R的免疫反应性可能是蜕膜化细胞之间旁分泌相互作用的证据，或者是催乳素具有免疫调节作用的证据。
