The effect of 6-oxo-prostaglandin E1 on human platelet aggregation in whole blood in-vitro.
The effect of PGI2, 6-oxo-PGE1 and PGE1 on ADP-induced human platelet aggregation has been assessed in whole blood and in blood centrifuged to prepare platelet-rich plasma (PRP). PGI2 was the most potent anti-aggregatory agent in both media. The concentration of PGI2 required to produce 50% inhibition of platelet aggregation was approximately 0.3 ng ml-1 in each case. In contrast both E series prostaglandins exhibited significantly greater (400-700%) anti-aggregatory activity when tested in whole blood than when tested in PRP. Since whole blood presumably represents a truer reflection of platelet reactivity in-vivo, we believe that the potency of 6-oxo-PGE1 (and PGE1) as inhibitors of platelet aggregation has been underestimated in previous experiments using PRP. In human whole blood 6-oxo-PGE1 has approximately 40% the anti-aggregatory activity of PGI2. The reasons for the increased anti-aggregatory potency of E series prostaglandins in whole blood is not known. We suggest that 6-oxo-PGE1 and PGE1 (but not PGI2) may prevent the release of pro-aggregatory ADP from red blood cells thereby enhancing their ability to inhibit platelet aggregation.
Wilsoncroft
P S
PS
Lofts
F J
FJ
Griffiths
R J
RJ
Moore
P K
PK
D000328:Adult; D000527:Alprostadil / Q000031:analogs & derivatives; D004305:Dose-Response Relationship, Drug; D011464:Epoprostenol / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects*; D011458:Prostaglandins E / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*
D011458:Prostaglandins E; D014665:Vasodilator Agents; C022950:6-ketoprostaglandin E1; D011464:Epoprostenol; D000527:Alprostadil