Figure 2

Effect of an nitric oxide (NO) synthase (NOS) inhibitor, NO scavenger, and guanylyl cyclase inhibitor on Polygonum viviparum (PV)-induced relaxation in isolated rat aorta. Acetylcholine (ACh) at 10 μM and 100 μg/ml PV (traces A and B, respectively) were treated after 3 μM phenylephrine (PE)-induced vasocontraction reached the maximal force in intact aorta. Prior to the addition of 100 μg/ml PV, the aorta was pretreated with 50 μM l-NAME (trace C), 5 μΜ hemoglobin (Hb) (trace D), and 10 μM methylene blue (MB) (trace E) for 6 min followed by the addition of PE. Each experiments was conducted in aortic rings of at least 5 animals.