Continuous monitoring of prostacyclin production by the isolated, intact, rat aorta using a bioassay technique.
Isolated rat aortae were perfused with Krebs buffer in vitro and the synthesis of prostacyclin-like material (PGI2-L) was continuously monitored by measuring the contraction of a superperfused rat stomach strip exposed to the aortic perfusate. PGI2-L release was high after initiation of the aorta perfusion but then gradually declined and stabilized at a basal rate of production that was maintained for at least 180 min. Levels of 6 keto prostaglandin F1 alpha(6ketoPGF1 alpha), the stable breakdown product of PGI2, in the aortic perfusate reflected the changes in biological activity. The concentration of PGE2 in the aortic perfusate remained constant throughout the experiment while the level of thromboxane (Tx)B2 (the stable product of TxA2) decreased with time to below the level of detection of the radioimmunoassay (RIA) used. All biological activity was abolished by heating the aortic perfusate for 30 min at 37 degrees C, while perfusing with 30 microM indomethacin inhibited aorta PGI-L formation. Analysis (by linear regression) of the relationship between PGI2-L formation and the body weight or age of the animals used revealed that PGI2-L synthesis was better related to body weight (r2 = 0.90) than age (r2 = 0.75).
D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism; D000375:Aging; D000818:Animals; D001011:Aorta / Q000378:metabolism; D001681:Biological Assay; D001835:Body Weight; D011464:Epoprostenol / Q000096:biosynthesis*; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D010477:Perfusion / Q000295:instrumentation; D051381:Rats; D011919:Rats, Inbred Strains
D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol; D007213:Indomethacin