Fig. 5.

Dilator responses of aortic rings to increasing concentrations of methacholine from mice under control conditions (open symbols: ○/☐) and following 8 wk of UCMS (filled symbols: ●/■). Data are presented under control conditions (A; control, lower bound = 16.6 ± 3.9%; UCMS, lower bound = 37.4 ± 4.6%), following pretreatment of rings with the H₂O₂ scavenger catalase (B; control + catalase, lower bound = 23.8 ± 4.4%; UCMS + catalase, lower bound = 72.3 ± 6.1%), or following combined treatment with catalase and l-NAME (C; control + catalase/l-NAME, lower bound = 91.4 ± 2.8%; UCMS + catalase/l-NAME, lower bound = 92.6 ± 3.1%). *P < 0.05 vs. responses in untreated vascular rings from control mice; †P < 0.05 vs. responses in untreated vascular rings from UCMS mice; n = 8 for control; n = 8–9 for UCMS.