Abstract The epithelial Ca 2+ channel (ECaC), which is exclusively expressed in 1, 25-
dihydroxyvitamin D 3-responsive tissues, ie, kidney, intestine, and placenta, is postulated to
constitute the initial step in the process of transcellular Ca 2+ transport. To strengthen this
postulated function, the present study compares the segmental and cellular distribution of
ECaC and the other Ca 2+ transport proteins known to be involved in transcellular Ca 2+
transport. In rabbit kidney, ECaC mRNA and protein expression were primarily present in the …