Fig 2. Experimental protocol and analysis of in vivo experiments.

(A,B) Representative screenshots from wild-type mice showing left ventricular pressure (mm Hg) over time during baseline, followed by 1 μM timolol, followed by the response to simultaneous addition of 1 μM cilostamide (Cil) and 10 μM rolipram (Rol) and lastly a second administration of timolol to verify responses to cilostamide and rolipram did not result from βAR activation. Displayed is the continuous recording of left ventricular pressure over the entire experimental period. The mice were pre-treated with either saline (A,C,E) or PTX (B,D,F; 120 μg/kg i.p. three days prior to study). Note that cilostamide and rolipram evoked an increase in pressure only in PTX treated mice in the presence of timolol. (C-F) Shown are individual contraction-relaxation cycles of changes in pressure from before and after addition of each respective drug administration expressed in mm Hg (C,D) or as a percentage of each individual maximal pressure (E,F; normalized to 100%) to illustrate the time base of the contraction-relaxation cycle. Cilostamide and rolipram increased pressure in AC5KO similar to WT but not in AC6KO (see Fig 3).