TRPV4 helps Piezo1 put the squeeze on pancreatic acinar cells.

Alterations in calcium signaling in pancreatic acinar cells can result in pancreatitis. Although pressure changes in the pancreas can elevate cytosolic calcium (Ca2+) levels, it is not known how transient pressure-activated elevations in calcium can cause prolonged calcium changes and consequent pancreatitis. In this issue of the JCI, Swain et al. describe roles for the mechanically activated plasma membrane calcium channels Piezo1 and transient receptor potential vanilloid subfamily 4 (TRPV4) in acinar cells. The authors used genetic deletion models and cell culture systems to investigate calcium signaling. Notably, activation of the Piezo1-dependent TRPV4 pathway was independent of the cholecystokinin (CCK) stimulation pathway. These results elegantly resolve an apparent discrepancy in calcium signaling and the pathogenesis of pancreatitis in pancreatic acinar cells.