Abstract

The anterior pituitary gland regulates growth, metabolism, and reproduction by secreting hormones. Folliculo-stellate (FS) cells are non-endocrine cells located among hormone-producing cells in the anterior pituitary glands. They form follicular lumens, which are sealed by tight junctions (TJs). Although FS cells are hypothesized to contribute to fine-tuning of endocrine cells, little is known about the exact roles of FS cells. Here, we investigated the molecular composition of TJs in FS cells. We demonstrated that occludin is a good marker for TJs in the pituitary gland and examined the structure of the lumens surrounded by FS cells. We also found that claudin-9 is a major component of TJs in the FS cells. In immunoelectron microscopy, claudin-9 was specifically localized at TJs of the FS cells. The expression of claudin-9 was gradually increased in the pituitary gland after birth, suggesting that claudin-9 is developmentally regulated and performs some specific functions on the paracellular barrier of follicles in the pituitary gland. Furthermore, we found that angulin-1, angulin-2, and tricellulin are localized at the tricellular contacts of the FS cells. Our findings provide a first comprehensive molecular profile of TJs in the FS cells, and may lead us towards unveiling the FS cell functions.

Highlights

  • The anterior pituitary gland regulates growth, metabolism, and reproduction by secreting hormones

  • We investigated the molecular composition of tight junctions (TJs) and tight junctions (tTJs) in FS cells by the quantitative reverse transcriptase-polymerase chain reaction, immunostaining, immunoprecipitation and immunoelectron microscopy, and found that claudin-9 is localized at the TJs of FS cells

  • Since it has been reported that occludin is expressed in the endothelial TJs in the central nervous ­system[33], we examined whether the occludin-positive cells include endothelial cells of blood vessels

Read more

Summary

Introduction

The anterior pituitary gland regulates growth, metabolism, and reproduction by secreting hormones. Folliculo-stellate (FS) cells are non-endocrine cells located among hormone-producing cells in the anterior pituitary glands. They form follicular lumens, which are sealed by tight junctions (TJs). The anterior pituitary gland ( known as adenohypophysis) is an endocrine organ that secretes several hormones to regulate growth, metabolism, reproduction, and stress responses. It is believed that the combination of expressed claudins determines the physiological characteristics of paracellular permeability of the tissues Another four-transmembrane domain protein ­occludin[33] and the cytoplasmic plaque protein ZO-134 are major components of TJs in epithelial cells. We investigated the molecular composition of TJs and tTJs in FS cells by the quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), immunostaining, immunoprecipitation and immunoelectron microscopy, and found that claudin-9 is localized at the TJs of FS cells

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.