Radiofrequency Renal Denervation Prevents Further Progression of Hypertension and Decreases Renal Medullary Fibrosis in One‐year‐old Spontaneously Hypertensive Rats (SHR)

Abstract

We have reported that radiofrequency renal denervation (RF‐RDN) in SHR at 20‐weeks of age, decreased blood pressure (BP) and fibrosis in kidney cortex and medulla when rats were sacrificed at 6 months. However, whether RF‐RDN can have similar benefits in older rats remains unknown. This study examined whether performing RF‐RDN in older rats also has a beneficial effect on BP and renal fibrosis. Baseline systolic and diastolic BP (SBP/DPB) was measured (telemetry) in nine‐month‐old SHR and Wistar Kyoto rats (WKY). Groups of rats then received bilateral RF‐RDN or Sham‐RDN (SHR‐RDN, n=9; SHR‐Sham, n=10; WKY‐RDN, n=5; WKY‐Sham, n=8). Rats were then sacrificed at 12‐months of age. Kidneys were harvested, sectioned, and assessed for fibrosis by Masson's trichrome stain. A pathologist, who was blinded to treatment groups, evaluated each kidney section for fibrosis. Compared to SHR with Sham‐RDN, RF‐RDN prevented a further increase in systolic and diastolic BP from baseline (9‐month) in SHR as they aged to 12‐months (SHR‐Sham mmHg: 9‐month 193±4/127±4; 12‐month 207±3/142±5; SHR‐RDN mmHg: 9‐month 197±3/132±2; 12‐month 197±4/132±3). RF‐RDN did not alter SBP or DBP in aged WKY. One‐year‐old SHR with prior Sham‐RDN showed extensive renal fibrosis in kidney cortex and medulla. In contrast, RF‐RDN significantly decreased renal fibrosis in the medulla, but not cortex. There was no fibrosis in kidneys of age matched WKY. These findings suggest that RF‐RDN may be a potential therapy for halting progression of hypertension and decreasing medullary fibrosis in the aged population.Support or Funding InformationNIGMS of NIH U54 GM104940 LA CaTS Roadmap Scholar to JG. NIH P30GM106392 to DRK and JG.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.