Research Article

GLP-1 Relaxes Rat Coronary Arteries by Enhancing ATP-Sensitive Potassium Channel Currents

Figure 3

Effects of inhibitors on glucagon-like peptide-1- (GLP-1-) induced relaxation in the rat coronary artery (RCA). The rings were precontracted with 1 μM U46619. After the precontraction was sustained and steady in endothelium-preserved rings, L-NAME (0.1 mM), indomethacin (0.01 mM), 4-AP (1 mM), glyburide (1 μM), or iberiotoxin (0.1 μM) was added to the bath. When the contraction was steady again in the presence of one of the inhibitors, the GLP-1 concentration-relaxation curve was reconstructed. The relaxation of endothelium-denuded rings by GLP-1 was compared with that of endothelium-preserved rings isolated from the same rat. Relaxation is expressed as a percentage of precontraction. Data are mean ± standard deviation; n = 6; vs. control.
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