Semaglutide's blood pressure-lowering effect in mice depends on GLP-1 receptors in vascular smooth muscle cells — not endothelial or immune cells — and this same pathway drives its kidney filtration and sodium excretion benefits.
VSMC GLP-1R is the key targetEliminating GLP-1 receptors from vascular smooth muscle cells completely abolished semaglutide's blood pressure-lowering, GFR-increasing, and natriuretic effects while leaving weight and glucose effects intact
What the researchers found
GLP-1 receptors in vascular smooth muscle cells (VSMCs) are essential for semaglutide to lower blood pressure in mice. When VSMC GLP-1R expression was eliminated, semaglutide could no longer reduce blood pressure, despite continuing to reduce food intake, body weight, and blood glucose normally.
In contrast, GLP-1 receptors on Tie2+ endothelial cells and immune cells were dispensable — mice lacking GLP-1R in these cell types still showed normal blood pressure reduction with semaglutide. The VSMC GLP-1R was also required for semaglutide's effects on increasing glomerular filtration rate and promoting natriuresis (sodium excretion).
Proteomic analysis revealed that semaglutide treatment changed protein expression in the renal artery and kidney related to platelet aggregation, fibrin clot formation, lipid metabolism, and pro-apoptotic signaling — all abolished in mice lacking VSMC GLP-1R. Additionally, semaglutide directly relaxed pre-constricted blood vessels in an ex vivo artery preparation.
Why it matters
GLP-1 receptor agonists like semaglutide are among the most widely prescribed drugs in the world, with expanding indications beyond diabetes into cardiovascular and kidney disease. Understanding exactly how these drugs lower blood pressure — through vascular smooth muscle, not just weight loss or endothelial effects — is critical for designing next-generation therapies and predicting which patients will benefit most from the cardiovascular and renal protective effects.
How the study worked
The researchers used genetically engineered mice with GLP-1 receptors selectively deleted from specific cell types — vascular smooth muscle cells, Tie2+ endothelial cells, or immune cells. They administered semaglutide and measured blood pressure, food intake, body weight, blood glucose, glomerular filtration rate, and natriuresis. Proteomic analysis was performed on renal artery and kidney tissue to identify molecular pathways affected by VSMC GLP-1R signaling. Ex vivo vasorelaxation experiments were conducted on pre-constricted mesenteric arteries to test direct vascular effects.
What this study cannot tell us
The study was conducted in mice, and the specific cellular mechanisms may differ in humans. Blood pressure regulation in mice involves different hemodynamic parameters than in humans. The proteomic changes were observed in mouse kidney and renal artery tissue, and clinical relevance needs to be confirmed. Specific semaglutide doses and treatment durations were not detailed in the abstract.
How to read the evidence
This is a high-quality preclinical mechanistic study using cell-type-specific genetic knockouts in mice, proteomic analysis, and ex vivo functional assays. Published in JCI Insight from a leading GLP-1 research laboratory, it provides strong mechanistic evidence but requires clinical validation in humans.
When this study was published
Published in 2026, this is a brand-new study representing the cutting edge of GLP-1 receptor biology research at a time when GLP-1 agonists are among the most prescribed drug classes globally.
The bigger picture
This study from Daniel Drucker's lab — one of the leading GLP-1 research groups globally — fundamentally shifts understanding of how GLP-1 drugs affect the cardiovascular system. The previous assumption was that blood pressure reduction came primarily from weight loss and endothelial nitric oxide signaling. Identifying vascular smooth muscle as the key cellular target opens new avenues for drug development and helps explain why GLP-1 agonists reduce cardiovascular events even before significant weight loss occurs.
Questions still open
- Do these vascular smooth muscle GLP-1R mechanisms translate to the blood pressure-lowering effects seen in human clinical trials of semaglutide?
- Could drugs targeting the VSMC GLP-1R pathway specifically be developed for blood pressure reduction without the metabolic effects?
- Does this mechanism explain why some patients experience greater cardiovascular benefits from GLP-1 agonists than would be expected from weight loss alone?
Common questions
What does this mean for people taking semaglutide (Ozempic/Wegovy)?
Why did scientists previously think semaglutide lowered blood pressure through different mechanisms?
Read the original research
Semaglutide Reduces Murine Blood Pressure Through the Vascular Smooth Muscle GLP-1 Receptor.
JCI insight
Citation
Medak, Kyle D; Koehler, Jacqueline A; Baggio, Laurie L; Gonzalez-Rellan, Maria J; Wong, Chi Kin; Cao, Xiemin; Rao, Vivikta; Kao, Sean; Cui, Yu; Fu, Jiayi; Liaw, Easton; Kabir, M Golam; Zhang, Jie; Wei, Jin; Drucker, Daniel J. (2026). Semaglutide Reduces Murine Blood Pressure Through the Vascular Smooth Muscle GLP-1 Receptor.. JCI insight. https://doi.org/10.1172/jci.insight.201148