Figure 3.

Involvement of calcium regulation in nuciferine‐induced relaxation. CaCl₂‐induced dose‐dependent contractions in the absence and presence of nuciferine (1 or 10 μM) in arterial rings without endothelium in Ca²⁺‐free depolarizing solution, with nifedipine as a positive control (A). In (B), the effects of nuciferine on the contractile response of arterial rings to phenylephrine (Phe). *P < 0.05, significantly different from control (DMSO). In (C), The mechanism mentioned earlier is associated with the intracellular and/or extracellular Ca²⁺ regulation (C). Contractile response of each segment is expressed as a percentage of contraction by KCl (60 mM). Data shown are means ± SEM; n = 5. *P < 0.05, significantly different from control (phenylephrine), ^# P < 0.05 compared with control (CaCl₂)