2. The mechanisms of NsaiDs Cyclooxygenases: COX1, COX 2 PGS, mostly by cox-1, are constitutively expressed in almost all tissues; COX-2 appears to only be constitutively expressed in the brain, kidney, bones, reproductive organs, and some neoplasms Under normal physiologic conditions, PGs play an essential homeostatic role in cytoprotection of gastric mucosa, hemostasis, renal physiology, gestation, and parturition In platelets there is only COX-lexist(converts arachidonic acid to TxA2 COX-1 predominant in gastric mucosa(source of cytoprotective PGs) The production of PGs, (inducible COX-2 activity > COX-1)at sites of inflammation propagate pain, feverCyclooxygenases: COX 1, COX 2 - PGs, mostly by COX-1, are constitutively expressed in almost all tissues; COX-2 appears to only be constitutively expressed in the brain, kidney, bones, reproductive organs, and some neoplasms - Under normal physiologic conditions, PGs play an essential homeostatic role in cytoprotection of gastric mucosa, hemostasis, renal physiology, gestation, and parturition - In platelets there is only COX-1exist (converts arachidonic acid to TxA2 ) - COX-1 predominant in gastric mucosa (source of cytoprotective PGs) - The production of PGs, (inducible COX-2 activity >> COX-1) at sites of inflammation propagate pain, fever 2. The mechanisms of NSAIDs