TY - JOUR
T1 - Prostaglandins and human platelet aggregation. Implications for the anti-aggregating activity of thromboxane-synthase inhibitors
AU - Rajtar, Grazyna
AU - Cerletti, Chiara
AU - Castagnoli, Maria Novella
AU - Bertelé, Vittorio
AU - de Gaetano, Giovanni
PY - 1985/2/1
Y1 - 1985/2/1
N2 - Selective pharmacological blockade of thromboxane-synthase in human platelets by dazoxiben resulted in the reorientation of cyclic-endoperoxides towards PGE2, PGD2 and PGF2α. At concentrations which can be reached when thromboxane-synthase is inhibited, PGE2 (100-500 nM) exerted a marked, concentration-dependent pro-aggregatory effect. This required the formation of endogenous or the addition of exogenous endoperoxides and was prevented by PGD; or 13-aza-prostanoic acid, a selective antagonist of PGH2/TxA2 receptors. The anti-aggregating effect of PGD2 was evident at concentrations lower than those obtained in dazoxiben-treated platelets. It is proposed that in the absence of TxA2 generation, a combination of endoperoxides and PGE2 may result in normal aggregation. The latter may be inhibited by PGD2. No interference of PGF2α on platelet function could be shown.
AB - Selective pharmacological blockade of thromboxane-synthase in human platelets by dazoxiben resulted in the reorientation of cyclic-endoperoxides towards PGE2, PGD2 and PGF2α. At concentrations which can be reached when thromboxane-synthase is inhibited, PGE2 (100-500 nM) exerted a marked, concentration-dependent pro-aggregatory effect. This required the formation of endogenous or the addition of exogenous endoperoxides and was prevented by PGD; or 13-aza-prostanoic acid, a selective antagonist of PGH2/TxA2 receptors. The anti-aggregating effect of PGD2 was evident at concentrations lower than those obtained in dazoxiben-treated platelets. It is proposed that in the absence of TxA2 generation, a combination of endoperoxides and PGE2 may result in normal aggregation. The latter may be inhibited by PGD2. No interference of PGF2α on platelet function could be shown.
U2 - 10.1016/0006-2952(85)90036-X
DO - 10.1016/0006-2952(85)90036-X
M3 - Articolo
VL - 34
SP - 307
EP - 310
JO - Biochemical Pharmacology
JF - Biochemical Pharmacology
SN - 0006-2952
IS - 3
ER -