Distribution and activity factors of TRPV2 and TRPV4 in LUT. TRPV2 and TRPV4 are distributed in many areas of the LUT, and both channels are activated leading to influx of ions, but the specific mechanisms differ, with TRPV2 being activated by heat and lysophosphatidylcholine (LPC) leading to influx of calcium and sodium ions. TRPV4 in the presence of stretch, chemical stimulation, and 4αPDD is activatable and ultimately stimulates cells to release ATP to activate P2X channels and downstream G protein-coupled receptors (GPCRS), eliciting downstream responses.