title: Prostaglandin E2 synthesis in pigeon aorta: comparison of atherosclerosis-resistant (Show Racer) and atherosclerosis-prone (White Carneau) breeds.
abstract: Microsomes prepared from the brachial artery and the thoracic aorta of atherosclerosis resistant (AR) Show Racer and atherosclerosis prone (AS) White Carneau pigeons were incubated with 14C-prostaglandin endoperoxide (PGH) and prostaglandin products analyzed. The microsomes demonstrated minimal prostacyclin (PGI2) synthetase activity; 6-keto-PGF1 alpha (the hydrolytic breakdown product of PGI2) accounting for less than 2% of total products. Reduced glutathione enhanced PGE2 formation in both the AR and AS preparations identifying an active PGH-PGE isomerase. The AR preparations demonstrated increased PGH-PGE formation with age, reaching maximal activity at 8-9 months, then decreasing at 14 months. The AS group also demonstrated a similar pattern of enzyme activity. These studies indicate that a) unlike the mammalian preparations prostacyclin synthetase does not appear to be a major enzymatic activity of the pigeon aorta, rather, b) PGH-PGE isomerase is the major endoperoxide metabolizing activity in the pigeon aorta and thus, c) a deficiency of prostacyclin production is not involved in the geneis of atherosclerosis in the pigeon.
mesh_terms: D000375:Aging; D000818:Animals; D001011:Aorta / Q000032:analysis*; D001161:Arteriosclerosis / Q000097:blood*; D010856:Columbidae; D005978:Glutathione / Q000494:pharmacology; D008861:Microsomes; D011457:Prostaglandins D / Q000096:biosynthesis; D011458:Prostaglandins E / Q000096:biosynthesis*; D011460:Prostaglandins F / Q000096:biosynthesis; D011463:Prostaglandins H / Q000096:biosynthesis
chemical_list: D011457:Prostaglandins D; D011458:Prostaglandins E; D011460:Prostaglandins F; D011463:Prostaglandins H; D005978:Glutathione