231-LB: GLP-1 Promotes Cortical and Medullary Perfusion in Human Kidney and Maintains Tissue Oxygenation during Na Loading

Purpose: GLP-1 receptor agonism has shown beneficial cardiovascular effects which could include the kidneys. In the human kidney, the high GLP-1 extraction and its natriuretic effect depend on the GLP-1 receptor and is accompanied by suppression of angiotensin II, independent of changes in renal plasma flow. Preclinical data showed that angiotensin II constricts the vasa recta and lowers medullary perfusion. The current randomized, controlled study was designed to test the hypothesis that GLP-1 increases renal medullary perfusion in healthy humans. Methods: Healthy male participants (n=10, 27 ± 4 years) ingested a fixed sodium intake for 4 days and were examined twice during a 1-hour infusion of either GLP-1 (1.5 pmol/kg/min) or placebo together with infusion of 0.9% NaCl (750 mL/h) . Interleaved measurements of renal artery flow, oxygenation (R2*) , and perfusion were acquired in the renal cortex and medulla during infusions, using magnetic resonance imaging. Results: GLP-1 infusion increased medullary perfusion (32 ± 7%, p