Hypoxic vasodilation in porcine coronary artery is preferentially inhibited by organ culture

J. Paul. Hypoxic vasodilation in porcine coronary artery is preferentially inhibited by organ culture. Am J Physiol Cell Physiol 281: C24–C32, 2001.—Hypoxia (95 % N2-5 % CO2) elicits an endothelium-independent relaxation (45–80%) in freshly dissected porcine coronary arteries. Paired artery rings cultured at 37°C in sterile DMEM (pH;7.4) for 24 h contracted normally to KCl or 1 mM U-46619. However, relaxation in response to hypoxia was sharply attenuated compared with control (fresh arteries or those stored at 4°C for 24 h). Hypoxic vasorelaxation in organ cultured vessels was reduced at both high and low stimulation, indicating that both Ca21-independent and Ca21-dependent compo-nents are altered. In contrast, relaxation to G-kinase (sodium nitroprusside) or A-kinase (forskolin and isoproterenol) acti-vation was not significantly affected by organ culture. Addi