Related Experiment Video
Updated: Aug 13, 2026
Isolation of Sertoli Cells and Peritubular Cells from Rat Testes
Published on: February 8, 2016
Prolactin receptor expression in rat spermatogenic cells
E Hondo1, M Kurohmaru, S Sakai
1Department of Veterinary Anatomy, Faculty of Agriculture, University of Tokyo, Japan.
Abstract:
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.
Insights
Prolactin receptors (PRL-R) mRNA and binding sites are present in adult rat testes, including Leydig, Sertoli, and various spermatogenic cells. This suggests prolactin may directly influence sperm development.
Area of Science:
- Reproductive Biology
- Endocrinology
- Cell Biology
Background:
- Prolactin (PRL) is a hormone with diverse functions.
- Its role in the male gonad is not fully understood.
- Identifying PRL target cells is crucial for understanding male reproductive physiology.
Purpose of the Study:
- To investigate the expression of prolactin receptor (PRL-R) mRNA in adult rat testes.
- To determine the binding of PRL to testicular cells in vitro.
- To identify specific testicular cell types targeted by prolactin.
Main Methods:
- In situ hybridization using a digoxigenin-labeled cRNA probe to detect PRL-R mRNA.
- In vitro studies to assess PRL binding to testicular cells.
- Analysis of PRL-R expression across different stages of spermatogenesis and in interstitial cells.
Main Results:
- PRL-R mRNA was detected in interstitial cells (Leydig and Sertoli cells) and spermatogenic cells (spermatogonia, spermatocytes).
- PRL-R mRNA expression was observed in all stages of the seminiferous epithelium cycle.
- PRL binding was confirmed on Leydig cells, Sertoli cells, spermatogonia, spermatocytes, elongated spermatids, and spermatozoa, with notable binding on Leydig cells, pachytene spermatocytes, and spermatozoa.
Conclusions:
- PRL-R mRNA expression and PRL binding sites largely overlap in rat testes, except for elongated spermatids and spermatozoa.
- Prolactin likely exerts direct effects on various testicular cells, including those involved in spermatogenesis.
- These findings contribute to understanding the endocrine regulation of male reproduction.
