Validity of Vascular Prostaglandin Assay Methods

This study directly compares the three major methods of prostaglandin as say for explanted blood vessels in an effort to determine whether reliable assays can be performed on small, localized areas. Under general anesthesia, canine femoral arteries and veins (n =16) were excised after measurement of in vivo dimensions. Each vessel was divided into three segments. Vessel segments were (1) incubated as whole rings ("biopsy" method), (2) incubated with the luminal surface covered by a plexiglass well (well method), or (3) perfused with a pulsa tile pump at physiologic pressure, temperature, and flow rate for two fifteen minute cycles with a balanced salt solution (perfusion method). Perfusion seg ments were also tested by the well and biopsy methods after thirty minutes of ex vivo perfusion. Assays of stable metabolites for prostacyclin (Pc) and throm boxane A2 (Tx) were performed using commercially available radioimmuno assay techniques. Luminal perfusion was used as the "gold standard" for corre lation.Mea...