Prostacyclin receptors PGI2 binding

We had the opportunity to analyse whole human blood obtained directly via a catheter from the lung arteries and veins. The blood samples were from heparinised patients which underwent a diagnostic study for heart function and performance. We preferred to analyse whole blood rather than plasma in order to include in our assay also the PGI2 possibly bound to receptors of the formed elements of the blood (especially of the platelets but even the erythrocytes have been reported to bind prostacyclin). The blood (10 ml) was immediately collected in 20 ml ethylalcohol in which 10 ng u)-homo-6keto-PGF.j was present as an internal standard. The samples were kept at -20°C until analysis. 

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