Radiofrequency Renal Denervation Produces Sustained Decreases in Blood Pressure and Cytokines, Tumor Necrosis Factor α (TNF α) and Interleukin 17 (IL‐17), in Spontaneously Hypertensive Rats (SHR)

Radiofrequency ablation (RF‐ABL) of renal arteries decreases blood pressure (BP) and sympathetic activity in hypertensive SHR. We investigated whether the hypotensive action of RF‐ABL is associated with alteration in systemic inflammatory cytokines. Methods : 19 week‐old SHR and Wistar Kyoto rats (WKY) were distributed into four groups: sham WKY, RF‐ABL WKY, sham SHR and RF‐ABL SHR. After 3 days baseline BP recording (telemetry), rats received bilateral RF‐ABL or sham procedure (Biosense Webster Stockert 70 generator and RF‐probe). Following 4 weeks of BP recording, kidneys and brains were collected and TNFα and IL‐17 levels determined via ELISA. Results : 4 weeks following treatment, mean BP was significantly decreased in RF‐ABL SHR (Δ ‐8±2 mmHg; n=6) as compared to sham SHR (Δ 5±1 mmHg; n=6). RF‐ABL/sham did not alter BP in normotensive WKY (RF‐ABL, Δ 1±1, n=6; sham, Δ ‐1±1 mmHg, n=5). Kidney TNFα levels were reduced in RF‐ABL SHR compared to sham SHR (180±3 vs 221±6 pg/mg protein), and RF‐ABL trended to decrease TNFα levels in SHR hypothalamus. IL‐17 levels were reduced in kidneys and hypothalamus of RF‐ABL SHR compared to sham SHR (kidney, 52.3±0.8 vs 63.5±1.4; hypothalamus, 31.8±4.4 vs 49.1±4.2, pg/mg protein). RF‐ABL did not alter TNFα or IL‐17 levels in WKY. Conclusion : RF‐ABL produced a sustained reduction in BP in hypertensive SHR which was associated with markedly decreased inflammatory cytokine proliferation in kidneys and hypothalamus. The reduction in cytokines may contribute to the beneficial hypotensive response produced by RF‐ABL in SHR, but not WKY. Biosense Webster IIS‐175 to DRK & FS; P20 GM103514 to DRK