Figure 4. Effects of l-NAME on forearm vasoconstrictor responses to tyramine during heavy rhythmic handgrip exercise.

The vasoconstrictor responses to tyramine are significantly blunted during heavy handgrip exercise (open bars) compared with a control vasodilator condition (adenosine; filled bars). NOS inhibition with l-NAME does not augment the vasoconstrictor responses during either adenosine or exercise. * P < 0.05vs. adenosine within same l-NAME condition.