Effects of sCD40L on eNOS mRNA levels and endothelium-dependent vasorelaxation in porcine coronary arteries. (A) Porcine eNOS mRNA levels. Porcine coronary artery rings were treated with sCD40L (5 μg/mL) for 24 hours, and porcine eNOS mRNA levels were determined by real-time PCR. *P < .05 compared with the control. t test. n = 4. (B) Endothelium-dependent vasorelaxation. Porcine coronary artery rings were treated with sCD40L for 24 hours. Vasomotor reactivity was analyzed with a myograph device. The vessel ring was initially contracted with thromboxane A2 analog U46619, and then a relaxation concentration-response curve was generated by 4 cumulative additions of the endothelium-dependent vasodilator bradykinin. *P < .05 compared with the control. U test. n = 8. Data are means and SE of multiple experiments (n).