Inositol trisphosphate receptors

Inositol trisphosphate receptors (IP3Rs) are proteins in cells that help control the release of calcium ions from internal stores. When a cell receives a signal—like a hormone—they open up and allow calcium to flow out into the cytoplasm. This increase in calcium levels acts like a message that triggers various cellular processes, such as muscle contractions or hormone release. Essentially, IP3Rs play a critical role in how cells communicate and respond to different stimuli, making them important for many bodily functions.