@article{oai:nagasaki-u.repo.nii.ac.jp:00020222, author = {Yamaguchi, Koji and Szlam, Fania and Levy, Jerrold H. and Makita, Tetsuji}, issue = {3-4}, journal = {Acta medica Nagasakiensia}, month = {Dec}, note = {Internal mammary arteries (IMA) are routinely used for coronary artery bypass grafting (CABG), but can exhibit impairment of endothelium-dependent vascular relaxation. The use of radial artery (RA) grafts for CABG has been recently reintroduced. The long-term patency of these grafts may depend on the ability of these vessels to produce endotheliumderived nitric oxide (NO). We therefore sought to determine if the RA exhibits better endothelial function compared with IMA harvested from the same patient. Using the organ bath technique, vessels were preconstricted with the thromboxane A2 analogue (U46619) and exposed to increasing concentrations of either acetylcholine (ACh ), calcium ionophore A23187 (A23187), or nitroglycerin (NTG). We prepared the rubbed RA for comparison of between RA with and without endothelium on response to ACh relaxation. KCI and U46619 constricted RA (11.3ツア4.9g and 16.0ツア4.3g respectively) more than IMA(2.4ツア1.4g and 4.5ツア1.7 respectively). Both RA and IMA relaxed 100% of the preconstricted tension to NTG. ACh induced less relaxation in the IMA(28ツア24%) when compared with the RA(49ツア16%)(p<0.05). A23187 demonstrated relaxation in both the RA(86ツア14%)and IMA(76ツア18%), but there was no statistical difference. RA without endothelium showed same response to ACh as IMAs. Compared with the IMA, the RA has better ACh induced endothelium-dependent relaxation. This pathway mainly involves NO production which also inhibits the atherosclerotic process. Therefore, the RA may provide longer term graft patency than IMA., Acta medica Nagasakiensia. 2000, 45(3-4), p.33-37}, pages = {33--37}, title = {Pharmacological Comparison of Human Internal Mammary Artery and Radial Artery in Terms of Conduits for Revascularization}, volume = {45}, year = {2000} }