Scientists at the University of Virginia have made an important discovery that could lead to better treatments for high blood pressure and kidney disease.
Their research shows how our bodies naturally “turn off” a hormone called renin, which helps raise blood pressure when needed.
The study, led by Dr. R. Ariel Gomez and Dr. Maria Luisa S. Sequeira-Lopez, focuses on special kidney cells called juxtaglomerular cells. These cells release renin when blood pressure drops, helping to bring it back up. But too much renin can cause blood pressure to stay high all the time, leading to serious health problems.
The scientists discovered that the hormone angiotensin II, also known as ang II, helps control renin by affecting calcium levels inside the kidney cells. When ang II is present, calcium levels in these cells go up and down in short bursts called oscillations. These calcium changes tell the cells to stop making and releasing renin.
In the past, scientists looked at single kidney cells to try to understand this process. But this new research used whole kidney tissue, which gave a much clearer picture. The team found that calcium changes spread from one cell to nearby cells. This helps the kidney slow down renin production more effectively than if the signal stayed in just one cell.
Dr. Hiroki Yamaguchi, the first author of the study, said that calcium acts like a messenger in these cells. It helps the kidney respond to signals from hormones, blood pressure, and the nervous system, all at once. This means our bodies use a very fine-tuned system to manage blood pressure and keep it in a healthy range.
These new insights could lead to better ways to treat high blood pressure. Most current medications work by blocking what turns systems on.
But Dr. Gomez and Dr. Sequeira-Lopez believe that looking at what turns these systems off—the “brakes,” so to speak—might be an even better approach. By studying how to safely reduce renin production, doctors may be able to lower blood pressure more effectively and with fewer side effects.
