Effects of roflumilast on intracellular cAMP levels.

(A) Lung parenchymal explants were incubated for either 20 min or 2h with media and vehicle or with LPS (1 µg/mL) and vehicle or roflumilast at 1 nM or 100 nM. (B) Lung parenchymal explants were exposed to vehicle or roflumilast at 1 nM or 100 nM in the presence or absence of formoterol (10 nM) and with LPS (1 µg/ml) for 20 min. Tissue homogenates were then analyzed for cAMP by EIA. The data shown are the means ± S.E.M. for samples from four different donors. ^*p< 0.05 vs. vehicle control (A); ^*p< 0.05; ^**p< 0.01 vs. LPS, ^#p<0.05; ^{# #}p<0.01 vs. formoterol and LPS (B).