👉 Papillary, in medicine, is a type of cell that produces and secretes hormones. Papillae are found on the surface of cells called epithelial cells, which line the walls of small blood vessels called capillaries. These cells can produce several types of hormones, including growth factors like platelet-derived growth factor (PDGF), which stimulates proliferation and migration of cells. Papillary cells also play a crucial role in the regulation of blood pressure by secreting substances that help to