RCS from human platelets: is it only thromboxane?
To determine if inhibition of a rabbit aorta contracting substance (RCS) corresponds to inhibition of thromboxane synthetase human washed platelets were stimulated with thrombin. RCS formation was bioassayed on rabbit aorta strips in Tyrode solution containing selective blocking agents and thromboxane (TX)B2 in the same probes by specific radioimmunoassay. Dazoxiben inhibited the formation of TXB2 but not of RCS, whereas indomethacin inhibited both RCS and TX formation. The data indicate that the rabbit aorta cannot be used alone to predict inhibition of TX formation with specific TX synthetase inhibitors.
D000818:Animals; D001792:Blood Platelets / Q000378:metabolism*; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D011817:Rabbits; D013928:Thromboxane A2 / Q000096:biosynthesis / Q000097:blood*; D013929:Thromboxane B2 / Q000096:biosynthesis / Q000097:blood; D013931:Thromboxanes / Q000096:biosynthesis / Q000097:blood*
D007093:Imidazoles; D013931:Thromboxanes; C029166:dazoxiben; D013929:Thromboxane B2; D013928:Thromboxane A2; D007213:Indomethacin