Rat pancreatic acinar cells were pretreated with no additions or with IPA-3 (20, 30, 40, 50 and 60 μM) or Pir 3,5 (20, 40 and 60 μM) for 15 min and then incubated with no additions (control), with 0.3 nM CCK or 100 nM CCK for 3 min or with 1 μM TPA for 5 min and then lysed. Whole cell lysates were submitted to SDS-PAGE and transferred to nitrocellulose membranes. Membranes were analyzed using anti-pT402 PAK2 and total PAK2 was used to verify loading of equal amounts of protein. The bands were visualized using chemoluminescence and quantification of phosphorylation was assessed using scanning densitometry. Both a representative experiment of 4 others and the means of all the experiments are shown. * P< 0.05 vs. control, # P< 0.05 vs. IPA-3 alone, and $ P< 0.05 comparing stimulants (CCK or TPA) preincubated with 1% DMSO vs. stimulants pre-incubated with IPA-3.