Effects of renal denervation on endogenous ouabain in spontaneously hypertensive rats

Purpose: Toinvestigatetheroleofrenaldenervation(RDN)on endogenousouabain (EO)secretion in spontaneouslyhypertensive rats(SHR). Methods: Sixteen 12-week-old male SHR were randomly separated into the renal denervation group (RDNX group) and sham operation group (sham group), and eight age-matched Wistar Kyoto rats (WKY) were served as control group. EO concentrations, the Na+- K+-ATPase activity, and the expression of Na+-K+-ATPase were assessed. Results: EO levels in serum, kidneys and hypothalamus of sham group were higher than in RDNX group (p < 0.05). Renal Na+-K+-ATPase activity subjected to denervation surgery showed significantly reduction when compared with the sham groups (p < 0.05). A positive correlation existed between norepinephrine (NE) content and Na+-K+-ATPase activity in the kidney (r2 = 0.579). Renal Na+-K+-ATPase alpha 1 subunit mRNA expression was down-regulated in the RDNX group compared with the sham group (P < 0.05), while renal Na+-K+-ATPase beta 1 subunit mRNA expression was no statistical significance between the groups (P = 0.63). Immunohistochemical analysis showed that there were significant differences in the renal expression of Na+-K+-ATPase between the three groups (P < 0.05). Conclusion: These experiments demonstrate that RDN exerted an anti-hypertensive effect with reduction of EO levels and Na+-K+-ATPase activity and Na+-K+-ATPase alpha 1 subunit expression of kidney in SHR.