Trypsin and elastase activities in pancreatic acini isolated from WT and UCP2^-/- mice.

<p>Isolated pancreatic acini of 12 months old WT and UCP2^-/- mice were treated <i>in vitro</i> with cerulein (10 nmol/L) for up to 90 min. Subsequently, cleavage of rhodamine 110-labeled synthetic substrates for (A) trypsin and (B) elastase was recorded by cytofluorometry. To compare proteolytic activities, ΔF/Δt ratios were calculated and data expressed as (ΔF/Δt)_cerulein - (ΔF/Δt)_untreated (mean ± SEM, n = 36). *<i>P</i><0.05 (WT versus corresponding UCP2^-/- mice). The intracellular levels of trypsinogen (C) and proelastase (D) were assessed by incubating the lysates obtained from unstimulated WT- and UCP2^-/- cells of 12 months old mice with active trypsin as described in the “<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094494#s2" target="_blank">Materials and methods</a>” section. A value of 100 percent corresponds to the averaged activity of <i>in vitro</i>-activated trypsin from WT cells. Data are shown as mean ± SEM (n = 18). *<i>P</i><0.05 (WT versus corresponding UCP2^-/- mice).