Localization, distribution, and function of the calcium-sensing receptor in sperm.
Francisco J Mendoza1, Carlos C Perez-Marin, Luis Garcia-Marin
1Dept Medicina y Cirugia Animal, Universidad de Cordoba, Campus Universitario Rabanales, Ctra. Madrid-Cadiz km 396, Cordoba, Spain. pv2megaf@uco.es
Journal of Andrology
|March 12, 2011
Summary
This study identified the calcium-sensing receptor (CaSR) in sperm cells and testicular tissue. Activating CaSR with calcimimetics enhanced sperm motility without affecting viability.
Area of Science:
- Reproductive Biology
- Molecular Cell Biology
- Spermatology
Background:
- Intracellular calcium (Ca2+) movement via calcium channels is crucial for sperm function.
- The calcium-sensing receptor (CaSR), which detects extracellular calcium, has not been previously described in spermatozoa.
Purpose of the Study:
- To investigate the expression of CaSR in testicular tissue and sperm cells.
- To determine the functional consequences of activating spermatozoid CaSR using calcimimetics.
Main Methods:
- CaSR mRNA and protein expression were confirmed using real-time RT-PCR and immunohistochemistry in rat testicular tissue and spermatozoa.
- Sperm motility and viability were assessed in rat and pig sperm treated with the calcimimetic AMG 641, using computer-assisted sperm analysis and flow cytometry.
Main Results:
- CaSR mRNA and protein were successfully identified in rat testicular tissue and rat spermatozoa.
- Treatment with calcimimetic AMG 641 significantly increased rat sperm motility (from 1.0 ± 0.1 to 3.8 ± 0.3) and modestly improved pig sperm motility parameters.
- AMG 641 demonstrated efficacy across a range of concentrations (optimal at 50-100 nM) and did not negatively impact sperm viability.
Conclusions:
- Functional CaSR is expressed in testicular tissue and sperm cells.
- The calcimimetic AMG 641 can activate CaSR, leading to enhanced sperm motility without compromising sperm viability.
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