The requirement for TRPV6 for vitamin D-dependent intestinal calcium absorption in vivo has been examined by using vitaminD-deficient TRPV6 null mice and littermate wild-type mice. Each ofthe vitamin D-deficient animals received each day for 4 days 50 ngof 1,25-dihydroyvitamin D3 in 0.1 ml of 95 propylene glycol:5ethanol vehicle or vehicle only. Both the wild-type and TRPV6 nullmice responded equally well to 1,25-dihydroxyvitamin D3 in increasingintestinal calcium absorption. These results, along withour microarray data, demonstrate that TRPV6 is not required forvitamin D-induced intestinal calcium absorption and may not carryout a significant role in this process. These and previous resultsusing calbindin D9k null mutant mice illustrate that molecularevents in the intestinal calcium absorption process in response tothe active form of vitamin D remain to be defined.
展开▼
