Our previous study demonstrated the involvement of cystic fibrosis transmembrane conductance regulator (CFTR) in transporting bicarbonate that is necessary for sperm capacitation; however, whether its involvement is direct or indirect remains unclear. The present study investigated the possibility of a Cl−/HCO3– exchanger (solute carrier family 26, number 3 [SLC26A3]) operating with CFTR during guinea pig sperm capacitation. Incubating sperm in media with various concentrations of Cl− resulted in varied percentages of capacitated sperm in a concentration-dependent manner. Depletion of Cl−, even in the presence of HCO3−, abolished sperm capacitation and vice versa, indicating the involvement of both anions in the process. Capacitation-associated HCO3−-dependent events, including increased intracellular pH, cAMP production, and protein tyrosine phosphorylation, also depend on Cl− concentrations. Similar Cl− dependence and inhibitor sensitivity were observed for sperm-hyperactivated motility and for sperm-egg fusion. The expression and localization of CFTR and SLC26A3 were demonstrated using immunostaining and Western blot analysis. Taken together, our results indicate that Cl− is required for the entry of HCO3− that is necessary for sperm capacitation, implicating the involvement of SLC26A3 in transporting HCO3−, with CFTR providing the recycling pathway for Cl−.
How to translate text using browser tools
1 January 2009
Cl− Is Required for HCO3− Entry Necessary for Sperm Capacitation in Guinea Pig: Involvement of a Cl−/HCO3− Exchanger (SLC26A3) and CFTR
Wen Ying Chen,
Wen Ming Xu,
Zhang Hui Chen,
Ya Ni,
Yu Ying Yuan,
Si Chang Zhou,
Wen Wei Zhou,
Lai Ling Tsang,
Yiu Wa Chung,
Pia Höglund,
Hsiao Chang Chan,
Qi Xian Shi
ACCESS THE FULL ARTICLE
Biology of Reproduction
Vol. 80 • No. 1
January 2009
Vol. 80 • No. 1
January 2009
bicarbonate
CFTR
Chloride
SLC26A3
sperm capacitation