Fig. 2. Effect of endothelium denudation on vasoconstrictor response to phenylephrine. (A ) Vasoconstrictions are expressed as percentages of 60 mm KCl constriction and are presented as the mean ± SD. When the vessels exhibited the oscillation, both maximum (squares and solid line ) and minimum (circles and dotted line ) values were plotted. Endothelium denudation caused leftward shift in the phenylephrine concentration-effect curve and abolished the oscillation (n = 6). (B ) Effects of endothelium denudation on the amplitude of 10−5m phenylephrine-induced oscillation are summarized (n = 6). *Significantly different from control (P < 0.05).
