3326 Radiofrequency Renal Denervation Prevents Further Progression of Hypertension and Decreases Renal Medullary Fibrosis in One-year-old Spontaneously Hypertensive Rats (SHR)

OBJECTIVES/SPECIFIC AIMS: 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. METHODS/STUDY POPULATION: 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. RESULTS/ANTICIPATED RESULTS: 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. DISCUSSION/SIGNIFICANCE OF IMPACT: These findings suggest that RF-RDN may be a potential therapy for halting progression of hypertension and decreasing medullary fibrosis in the aged population.