Fig. 2

Effects of i.v. bolus injections of: (a) saline; (b) prazosin (Praz); (c) rauwolscine (Rauw); (d) the combination of Praz plus Rauw; or (e) propranolol (Prop) on the increases in heart rate (∆ Heart rate) produced by (S)-isometheptene (0.03-3 mg/kg, i.v.) in pithed rats. *P < 0.05 vs. the corresponding dose in the control curve; ^# P < 0.05 vs. the corresponding dose in the curve obtained after saline; n = 5 for each group