Fig. 7.

Representative figure of the concentration-dependent contractile effect of PE on smooth muscle under condition in which both vesicular and PE-induced transporter-mediated release of NA are impaired by reserpine pre-treatment and nisoxetine, respectively. The reuptake of NA is also inhibited by nisoxetine contributing to loss of releasable content of vesicles. Reserpinized mouse vas deferens (5 mg/kg i.p. 18 h). Note, the size of contractions induced by train (10 Hz, 20 shocks) at 0.1 Hz reduces by time and PE is still able to contract smooth muscle in a concentration-dependent manner. Take into account that smooth muscles to NA and PE (see Table 1) are supersensitive