Fig. 2. Molecular expression of Na⁺ and Cl⁻ transporters and Na⁺-permeable cation channels detected by RT-PCR in AVP neurons and the SON region. (a) Expression of mRNAs encoding NHE, AE, ENaC, and TRPM2 in AVP neurons. The pooled cytosol of 10 AVP neurons was used in RT-PCR for NHE1 (555base pairs (bp)), NHE2 (523 bp), NHE3 (498 bp), NHE4 (408 bp), NHE5 (415 bp), AE1 (451 bp), AE2 (551 bp), AE3 (518 bp), α-ENaC (576 bp), β-ENaC (463 bp), γ-ENaC (472 bp), TRPM2 (533 bp), or GAPDH (429 bp) (n=4-10). Sequence analyses showed that the above seven genes sizably detected in AVP neurons were completely matched to the sequences corresponding to their respective rat NHE1, NHE4, NHE5, AE2, AE3, TRPM2, and GAPDH. (b) Expression of mRNAs encoding ENaC in the SON region. The block of SON region was used in RT-PCR for rat α-ENaC, β-ENaC, γ-ENaC, and GAPDH (n=4). The above four genes expressed in the SON region were completely matched to the sequences corresponding to their respective mRNAs. RT (+) and RT (−) represent lanes with and without reverse transcriptase.