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Connexins and steroidogenesis in mouse Leydig cells
Dan Li1, Poonampreet Sekhon, Kevin J Barr
1Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 5C1, Canada.
Canadian Journal of Physiology and Pharmacology
|March 6, 2013
Summary
Leydig cells express connexin36 and connexin43 in gap junctions, which are essential for testosterone production. Connexin45 is also present but its role in steroidogenesis requires further investigation.
Area of Science:
- Endocrinology
- Cell Biology
- Reproductive Biology
Background:
- Connexin43 forms gap junctions in Leydig cells, but its absence does not impair testosterone production.
- The role of other connexins in Leydig cell steroidogenesis remains unclear.
Purpose of the Study:
- To identify additional connexins in mouse Leydig cells involved in steroidogenesis.
- To investigate the functional role of identified connexins in testosterone production.
Main Methods:
- Reverse transcription-polymerase chain reaction (RT-PCR) to screen for connexin expression.
- Pharmacological inhibition of gap junctional coupling using carbenoxolone and quinine.
- Immunolabeling to confirm connexin localization in testis sections.
Main Results:
- Connexin36 and connexin45 were found to be coexpressed with connexin43 in Leydig cells.
- Inhibition of gap junctional coupling significantly reduced testosterone output.
- Connexin36 and connexin43 were localized to Leydig cell gap junctions, while connexin45 showed a broader cellular distribution.
Conclusions:
- Connexins 36, 43, and 45 are coexpressed in mouse Leydig cells.
- Connexins 36 and 43 are integral components of Leydig cell gap junctions.
- Connexin36 and/or connexin45 may play a role in supporting Leydig cell steroidogenesis, warranting further study for connexin45.
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