COX1, full name Cyclooxygenase-1, is one of the two isoforms of cyclooxygenase (COX), with the other being COX-2. COX1 is a constitutive enzyme that is widely expressed in most tissues such as blood vessels, stomach, kidneys, and platelets. It is involved in platelet aggregation, vascular tone, gastric mucosal blood flow, and regulation of renal blood flow, helping to maintain the stability of cellular, tissue, and organ physiological functions. Compared to COX-2, COX1 is constitutively expressed and plays a role in the synthesis of physiological prostaglandins (PGs), which regulate normal tissue cell activities such as protecting the gastrointestinal mucosa and altering vascular tone. COX1 plays a smaller role in inflammatory damage compared to COX-2. Inflammation primarily stimulates monocytes, macrophages, etc., inducing the production of COX-2, which is a key link in triggering subsequent inflammatory responses.