Bicarbonate link to CF infertility

Cystic fibrosis (CF) is marked by defects in the cystic fibrosis transmembrane conductance regulator (CFTR) and is responsible for the decrease in the fertility characteristic of women with CF. CFTR conducts bicarbonate secretion (although it has been doubted whether this is physiologically significant), and bicarbonate has been implicated in contributing to the ability of sperm to fertilize eggs (sperm capacitation). CFTR and bicarbonate may therefore contribute to the decreased fertility observed in women with CF, but this has been poorly investigated. In the September 28 Nature Cell Biology, Xiao Fei Wang and colleagues at the Chinese University of Hong Kong have shown that CFTR controls uterine bicarbonate secretion and as a result, the ability of sperm to fertilize eggs (Nature Cell Biology, DOI:10.1038/ncb1047, September 28, 2003).

Wang et al. investigated the mechanisms of bicarbonate secretion in a mouse endometrial (uterine mucosal lining) epithelial culture using the fluorimetric measurement...