Figure 4.

Concentration-dependent contraction of the rabbit anococcygeus muscle induced by noradrenaline infusion into the perfusion fluid in control conditions (A) and in the presence of EFS (B). (C) The contraction to a single concentration of noradrenaline alone, with EFS, and with EFS and l-NOARG (300 μM). Noradrenaline infusion is shown by arrows. EFS and l-NOARG are shown by separate horizontal bars. The mechanogram is an original recording of the responses of one preparation and is representative of all experiments in this series (n = 4).