A new study has uncovered a crucial “pressure sensor” inside the kidney that helps regulate blood pressure and fluid balance. For decades, scientists knew the kidneys could sense changes in blood volume, but they lacked a clear mechanistic explanation. Now, researchers at Oregon Health & Science University (OHSU) and collaborating institutions have identified PIEZO2 as the protein responsible for this sensing ability.
PIEZO2 Triggers Hormonal Response to Blood Volume Changes
The study, published in Cell, shows that PIEZO2 functions as a mechanical pressure sensor in the kidney. When blood volume shifts, PIEZO2 helps initiate the release of renin—a hormone that activates the renin-angiotensin-aldosterone system (RAAS). This hormonal pathway plays a central role in maintaining stable blood pressure and regulating the body’s salt and water balance.
However, the researchers found that removing PIEZO2 causes the kidney to release excessive amounts of renin. This imbalance disrupts the RAAS and forces the kidneys to filter blood too rapidly, a condition that may contribute to long-term health problems.
A Surprising Discovery in Kidney Physiology
“We’ve known for decades that mechanical forces in the kidney help control renin, but we didn’t know what molecules were actually sensing those forces,” said lead author Rose Hill, Ph.D., an assistant professor at the OHSU School of Medicine and the Vollum Institute.
She added that finding PIEZO2 in these specific kidney cells was unexpected, given that the ion channel was primarily known as a touch sensor in the nervous system. According to Hill, the discovery reveals a major gap in our understanding of how kidneys maintain blood pressure.
Research Roots and Key Breakthroughs
Much of the foundational work emerged during Hill’s postdoctoral research with Ardem Patapoutian, Ph.D., a Scripps Research scientist and Nobel laureate known for discovering mechanosensitive ion channels like PIEZO2. Patapoutian also serves as co-corresponding author of the study.
Hill explained that the breakthrough came from an unexpected observation. “When we first saw PIEZO2 in these cells, it immediately caught our attention,” she said. “This protein can detect mechanical forces, and those same forces influence renin release. PIEZO2 turned out to be the missing link.”
As reported by medicalxpress, the researchers demonstrated that PIEZO2 enables the kidney to respond appropriately to both short- and long-term changes in blood volume, including dehydration or increased fluid intake. Without PIEZO2, the kidney behaves as if the body is perpetually low on blood volume.
Broader Impact on Blood Pressure Sensing
The findings also show that PIEZO2 functions as a pressure sensor beyond the nervous system. “PIEZO proteins act as pressure sensors in cardiovascular nerves,” Hill said. “Now we see that PIEZO2 also works inside the kidney. It highlights their importance in sensing blood pressure throughout the body.”
Future Research and Clinical Potential
Although the discovery does not immediately produce new therapies, Hill emphasized that it opens meaningful research pathways. “We don’t have effective drugs targeting these pressure-sensing channels yet,” she said. “But understanding this system could eventually help us treat conditions where the kidneys are repeatedly stressed by dehydration or low blood volume.”
She pointed to chronic kidney disease of unknown origin (CKDu)—a condition affecting many young agricultural workers in extremely hot climates—as one potential area of impact. “These workers experience repeated dehydration, and we still don’t know how that leads to early kidney failure,” she said. “If volume loss affects PIEZO2 or the renin-producing cells, this pathway could be part of the explanation.”