Hondo E, Kurohmaru M, Sakai S, Ogawa K, Hayashi Y
Department of Veterinary Anatomy, Faculty of Agriculture, University of Tokyo, Japan.
Biol Reprod. 1995 Jun;52(6):1284-90. doi: 10.1095/biolreprod52.6.1284.
To identify target cells of prolactin (PRL) in the male gonad, the expression of prolactin receptor (PRL-R) mRNA in adult rat testes was investigated by in situ hybridization using a digoxigenin-labeled cRNA probe. We also investigated PRL binding to testicular cells in vitro. Signals for PRL-R mRNA were detected not only in interstitial cells but also in spermatogenic cells. Although the reaction was positive in all phases of spermatogonia and spermatocytes, it disappeared in early round spermatids. No signals were detected in elongated spermatids or spermatozoa. The signal intensity varied among each phase of spermatogenic cells. PRL-R mRNA was expressed in all stages of the cycle of the seminiferous epithelium. PRL-R were detected on the surface of Leydig cells, Sertoli cells, all phases of spermatogonia and spermatocytes, elongated spermatids, and spermatozoa. Ovine PRL. did not bind to round spermatids. In Leydig cells, pachytene spermatocytes, and spermatozoa, PRL-R were observed in relatively large numbers. There were fewer receptors in other phases of spermatogenic cells. These results indicate that PRL-R mRNA expression is almost consistent with PRL binding sites except for elongated spermatids and spermatozoa, and suggest that PRL may have direct effects on spermatogenic cells.
为了鉴定雄性性腺中催乳素（PRL）的靶细胞，我们使用地高辛标记的cRNA探针，通过原位杂交技术研究了成年大鼠睾丸中催乳素受体（PRL-R）mRNA的表达情况。我们还在体外研究了PRL与睾丸细胞的结合。PRL-R mRNA的信号不仅在间质细胞中被检测到，在生精细胞中也被检测到。虽然在精原细胞和精母细胞的所有阶段反应均呈阳性，但在早期圆形精子细胞中信号消失。在长形精子细胞或精子中未检测到信号。生精细胞各阶段的信号强度有所不同。PRL-R mRNA在生精上皮周期的所有阶段均有表达。在睾丸间质细胞、支持细胞、精原细胞和精母细胞的所有阶段、长形精子细胞以及精子表面均检测到PRL-R。绵羊PRL不与圆形精子细胞结合。在睾丸间质细胞、粗线期精母细胞和精子中，观察到相对大量的PRL-R。在生精细胞的其他阶段受体较少。这些结果表明，除了长形精子细胞和精子外，PRL-R mRNA的表达与PRL结合位点几乎一致，提示PRL可能对生精细胞有直接作用。
