ABSTRACT
<p><b>OBJECTIVE</b>To determine the expression pattern of Slc26a3 gene in reproductive tract of male rodents to clarify whether the expression pattern is related to the subfertility observed in congenital chloride diarrhea (CLD) disease.</p><p><b>METHODS</b>The expression of Slc26a3 in mouse and rat epididymis has been studied with immunohistochemistry and Western blotting. Its developmental expression pattern in rat testis was detected by Western blotting, while both of immunofluorescence and Western blotting were used to localize the expression of Slc26a3 in mouse sperms. The potential change of Slc26a3 expression in CFTR (cystic fibrosis transmembrane conductance regulator) knockout mice and CFTR mutant mice was also detected with Western blotting.</p><p><b>RESULTS</b>The expression level of Slc26a3 gradually decreased along epididymis from its caput to corpus, then to its cauda part. This gradually decreasing expression pattern was also found in rat testis during development. Slc26a3 was localized mainly on the trunk of mouse sperm tail. In the testis and epididymis of CFTR knockout mice and CFTR mutant mice, no significant change of Slc26a3 expression was found.</p><p><b>CONCLUSION</b>Slc26a3 is expressed in male reproductive tract, and its expression pattern is related to the function. Thus, the subfertility observed in CLD disease may be related to the important role of SLC26A3 in acid-base regulation of epididymis.</p>