Figure 2. Effect of agonists in intact mesenteric arteries.
Contractions induced by high K+ and agonists in intact rabbit (A), chicken (B) and pigeon arteries (C) under the normal Ca2+ (2 mm)-containing conditions (n = 6). Before the experiments were started, strips were repeatedly stimulated with a cycle of high K+ for 3 min and rest for 10 min until the steady state contraction was obtained. PE, 30 μm phenylephrine; His, 30 μm histamine; ATP, 200 μm; PG, 1 μm prostaglandin F2α; ET-1, 1 μm endothelin-1. D and E show a summary of high K+- and agonist-induced contractions under the normal conditions (open column) and in the presence of 0.2 μm nicardipine (filled column) in rabbit and chicken MA, respectively (n = 4). *Significant difference from respective control contraction in the absence of nicardipine.