Figure 2. Production of nitrite and vasodilation of the porcine carotid artery for forward and reverse flow.

A, production of NO metabolite (nitrite) in the porcine carotid artery for forward and reverse flow with (○) and without l-Arg (•). The data represent mean ± s.d. The asterisk denotes statistical significance between groups at the respective flows (P < 0.05). B, the degree of vasodilatation was expressed as outer diameter ratio (D/D₀) of carotid arterial segment where D is the diameter at a given flow and D₀ is the diameter at zero flow with same pressure. The ratio was significantly larger during forward flow as denoted by the asterisk.