Specifically, we demonstrate that physiologically relevant stimulation of TRPV4 expression and activity in cystic cells by high KCl diet increases basal [Ca2+]i levels, partially restores mechanosensitivity, and causes intracellular AQP2 retention (reduced cAMP levels) to markedly slow the development and growth of renal cysts in PCK453 rats (Figure 8, right panel). The gene discussed is AQP2; the disease is cystic kidney disease.