Summary
± Carbocyclic thromboxame A2 (2.9×10−7 mol/l) contracted isolated rings of cat coronary artery. These contractions could be partly inhibited by low concentrations of nifedipine (50% inhibitory concentration —IC50=6.8×10−8 mol/l) and completely relaxed by papaverine. Relaxation of thromboxane-induced coronary spasm may contribute to the effectiveness of calcium antagonists in variant angina, which may be caused or exacerbated by thromboxane A2 release from platelets.
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Towart, R., Perzborn, E. Relaxation of carbocyclic thromboxane A2-induced contractions of isolated coronary arteries by nifedipine. Naunyn-Schmiedeberg's Arch. Pharmacol. 318, 249–251 (1982). https://doi.org/10.1007/BF00500488
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DOI: https://doi.org/10.1007/BF00500488