Functional TRPV6 channels are crucial for transepithelial Ca~(2+) absorption

摘要

Previous in vivo experiments revealed a role for TRPV6 in placental Ca~(2+) transport (27). Consistent with this hypothesis is the finding that calbindin-D9K gene expression is significantly reduced in placenta of TRPV6~(-/-) mice, whereas TRPV5 levels are unaffected, suggesting an association of TRPV6 and calbindin-Dgk in placental Ca~(2+) transport. Since a considerable amount of Ca~(2+) transport still occurs in TRPV6~(-/-) mice, it is implied that other channels contribute significantly to this process (27). Recently, gain-of-function polymorphisms of the TRPV6 gene have been found in Ca~(2+)-stone-forming patients, which might contribute to absorptive hypercalciuria (28). These findings suggest that TRPV6 is one of the key players in intestinal Ca~(2+) absorption in humans, although further studies are required to elucidate its precise role.