title: Prolactin receptor expression in human testis and accessory tissues: localization and function.
abstract: Experimental studies in animals have established prolactin (PRL) as a progonadal hormone that promotes the function of the testis and reproductive accessory glands. The present study investigated the localization of PRL receptor (PRL-R) expression in the human testis and accessory tissues. Expression of PRL-R was identified in human testis and vas deferens by RT-PCR, and further localized by immunohistochemistry to the Leydig cells and differentiating germ cells of the testis (developmental stages extending from pachytene spermatocytes to elongating spermatids). Positive staining for PRL-R was also clearly evident in the epithelium of vas deferens, epididymis, prostate and seminal vesicles. Functional activation of PRL-R was demonstrated in fresh samples of vas deferens collected at vasectomy by examination of the JAK/STAT (Janus kinase/signal transducer and activator of transcription) and MAP (mitogen-activated protein) kinase ERK (extracellular signal-regulated kinase) signalling pathways. Within the vas deferens, PRL induced rapid tyrosine phosphorylation of JAK 2 and STAT 5 (after 10 and 20 min respectively), and tyrosine and threonine phosphorylation of ERK 1 and 2 (after 5 min). The demonstration of function and localization of PRL-R presented here suggests multiple roles for PRL in the human male reproductive tract.
authors.affiliation: MRC Human Reproductive Sciences Unit, Centre for Reproductive Biology, 37 Chalmers Street, Edinburgh EH3 9EW, UK.
authors.forename: W M
authors.initials: WM
authors.lastname: Hair
authors.forename: O
authors.initials: O
authors.lastname: Gubbay
authors.forename: H N
authors.initials: HN
authors.lastname: Jabbour
authors.forename: G A
authors.initials: GA
authors.lastname: Lincoln
mesh_terms: D006801:Humans; D007150:Immunohistochemistry; D020935:MAP Kinase Signaling System / Q000502:physiology; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D011981:Receptors, Prolactin / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013737:Testis / Q000378:metabolism*; D014649:Vas Deferens / Q000378:metabolism*
chemical_list: D011981:Receptors, Prolactin; D012313:RNA; D020928:Mitogen-Activated Protein Kinases