Anatomy and Chemistry Basics
The Endocrine System
Although their major function is not the secretion of hormones, some organs contain specialized cells that produce hormones. These organs include the heart, the gastrointestinal tract, the placenta, the kidneys, and the skin.
In addition, all cells (except red blood cells) secrete a class of hormones called eicosanoids. These hormones are paracrines, or local hormones, that primarily affect neighboring cells. Two groups of eicosanoids, the prostaglandins (PGs) and the leukotrienes (LTs), have a wide range of varying effects that depend upon the nature of the target cell. Eicosanoid activity, for example, may impact blood pressure, blood clotting, immune and inflammatory responses, reproductive processes, and the contraction of smooth muscles.
