Decreased expression of Na+-H+ exchanger isoforms 1 and 3 in denervated spontaneously hypertensive rat kidney

To determine whether the sympathetic nerve plays a role in the regulation of Na+-H+ exchange (NHE) in the kidney of spontaneously hypertensive rats (SHR), we investigated the expression of NHE and NHE regulatory protein family (NHERF) in the denervated kidneys compared with intact kidneys. Twelve-week-old male SHR and age-matched Wistar Kyoto (WKY) rats were used. SHR were randomly assigned to the renal denervated (RDNX, n = 8) or Sham (n = 8) groups. The protein and mRNA expression of NHE1, NHE3, NHERF1 and NHERF2 were assessed in the kidney of the groups. Following the renal denervation, immunohistochemistry and western blot analysis showed that NHE1 and NHE3 protein were significantly decreased in the kidney compared with Sham group. NHERF1 protein expression was significantly increased in RDNX compared with Sham group, whereas NHERF2 protein expression was significantly decreased after renal denervation. Similar results were observed at the mRNA level of NHE1, NHE3, NHERF1 and NHERF2 expression. The present findings suggest that the renal sympathetic nervous system plays a role in the regulation of NHE1 and NHE3 in the kidney of SHR, and NHERF1 may be involved in the expression of NHE3 in the kidney of SHR.