# Eicosanoids --- **Eicosanoid** are a type of [[hormone]] that performs local signaling. They are formed from [[fatty acids]] that have been cleaved from the [[phospholipid|phospholipids]] of a cell's plasma membrane. Unlike some other hormones, a lot of different types of cells can synthesize eicosanoids, which make them useful for local signaling. They include [[prostaglandins]], thromboxanes, and [[leukotrienes]]. ___