 In animal models and human tissues, they act through TP to promote platelet responses and stimulate blood vessel contraction.Synthetic analogs of TXA2 that activate TP but are relatively resistant to spontaneous and metabolic degradation include SQ 26655, AGN192093, and EP 171, all of which have binding and activating potencies for TP similar to I-BOP.Several synthetic compounds bind to, but do not activate, TP and thereby inhibit its activation by activating ligands.