Figure 2.

Differences in the regulation of cAMP dynamics by PDEs between pre-mature and mature murine transgenic brown adipocytes under β₁-AR activation. Representative FRET traces from cytosolic FRET sensor in pre-mature and mature BAs of β₁-AR activation by selectively blocking β₂-AR with 50 nM ICI 118551 and stimulation by 100 nM ISO followed by (A, D) PDE2 inhibitor BAY 60-7550 (BAY, 100 nM) (B, E) PDE3 inhibitor Cilostamide (Cilo, 10 μM) (C, F) PDE4 inhibitor Rolipram (Roli, 10 μM) with subsequent maximal FRET response achieved by inhibition of multiple PDEs with IBMX (100 μM). (G) Quantification of FRET responses to individual family-selective (PDE 2, 3 or 4) inhibitors upon β₁-AR stimulation are shown as a percentage of the maximal PDE inhibition obtained using the unselective inhibitor IBMX. n = 6-8. Bar graphs represent means ± S.E.M. Two-way ANOVA followed by Sidak's multiple comparison test was performed, significant differences correspond to ∗- p < 0.05.