Fig. 3.

The perfusion pressure changes in isolated mesenteric vascular beds with an intestinal tract, induced by phenylephrine or angiotensin II. (A) Phenylephrine at doses of 7.5 to 60 nmol was applied to the vascular bed in the absence (Control) or presence of 30 nmol/l prazosin (Prazosin) or 1 µmol/l naloxone (Naloxone). (B) Angiotensin II (Ang II; 400 pmol)-induced contraction in the absence (Control) or presence of 1 µmol/l naloxone (Naloxone). Data are shown as the mean ± S.E.M. of five rats. *P<0.05, vs. Control. ^#P<0.05, Naloxone vs. Prazosin. Repeated-measures two-way ANOVA, Tukey’s multiple comparison test.