Thromboxane A2 receptor density increases during chronic exposure to thromboxane A2 receptor antagonists after porcine carotid bypass

Abstract Domestic swine ( n =12 in each group) were randomized to daily treatment with the thromboxane A 2 (TXA 2 ) receptor antagonist BMS-180291 (group I), aspirin (group II), or no drug (group III) prior to prosthetic carotid graft implantation. Platelet and arterial wall receptor density were measured by equilibrium binding using 125 I-BOP. At 6 weeks, means (s.e.m.) platelet receptor density (pmol/mg) had increased in groups I (3.3(0.6) versus 1.8(0.3); P lt0.05) and II (2.6(0.6) versus 1.7(0.2); P versus 1.2(0.2)). Aortic membrane TXA 2 receptor density (fmol/mg) was significantly greater ( P 2 receptor antagonist or aspirin is associated with increased platelet and aortic receptor density in pigs. Published by Elsevier Science Ltd.