Prostaglandin E2 biosynthesis: changes in rabbit aorta and skin during experimental atherogenesis

The transformation of [1-14C]arachidonic acid into [14C]prostaglandin E2(PGE2) by rabbit aorta and skin was demonstrated by cell-free preparations, and the PGE2 synthetase activity was located mainly in the microsomal fraction (105,000 g pellet) of both tissues. Rabbits fed an atherogenic diet (Purina rabbit chow plus 1% cholesterol and 2% cottonseed oil) developed atheroma in the aortas and skin lesions resembling xanthoma in 6 to 7 months. At the end of this period, increases in the conversion of [1-14C]-arachidonic acid into [14C]PGE2 were observed in microsomal preparations of the intima-media of the aortas (2.5-fold of control) and normal-appearing skin (3.0-fold of control) of the experimental animal. Microsomal preparations of skin lesions particularly had greater ability to form PGE2 (7-fold of control).