Fig. 4

Effects of yohimbine, rauwolscine, and prazosin on contraction tension induced with 60 mM KCl and with dexmedetomidine (Dex)-enhanced responses to 60 mM KCl. Each drug was used at a concentration of 5 μM. Changes in contraction tension were normalized to 60 mM KCl in each set and expressed as a relative value (in percents). Statistical analysis was performed with Student’s t test between the means of two groups and one-way analysis of variance followed by Scheffe’s multiple comparison procedure among the three groups. Each bar and accompanying line indicate the mean and SE of a group. Six samples were included per group. *P < 0.05, compared with 60 mM KCl or Dex. C, control; Y, yohimbine; R, rauwolscine; P, prazosin; D, dexmedetomidine