15pinane thromboxane a2

15(R)-Pinane thromboxane A2 is the (R)-epimer of pinane thromboxane A2 . 15(R)-PTA2 does not inhibit collagen-induced platelet aggregation (IC50s = 120-130 μM). It does not affect gastric tone in isolated rat gastric fundus when used at concentrations of 0.5 or 1.5 μg ml and is less effective than PTA2 at inhibiting prostaglandin-induced contraction of isolated rat stomach muscle.