Table 1. Segmental distribution of proteins used for the identification of tubular segments in C57BL/6 micea

TALDCT earlyDCT lateCNTCCD
a Protein abundance: + weak; ++ intermediate; +++ strong; TAL, thick ascending limb; DCT, distal convoluted tubule; CNT, connecting tubule; CCD, cortical collecting duct; NKCC2, Na+-K+-2Cl Cotransporter 2; NCC, Na+-Cl Cotransporter; ENaC, epithelial Na+ channel; TRPV5, transient receptor potential, vanilloid-receptor related ion channel 5; NCX, Na+-Ca2+ exchange; CB, calbindin D28k; PV, parvalbumin.
b Rarely, weak PV immunostaining is also present in TAL and late DCT cells, whereas strong PV immunostaining is always visible in early DCT cells. These observations are consistent to two previous studies on C57BL/6 mice (27) (9), but are at variance to reports on NMRI mice that described high levels of PV in both early and late DCT (54).
NKCC2+++
NCC+++++
ENaC+++++++
AQP2+++++
TRPV5+++++
NCX++++++
CB+++++++
PVb+++