BACKGROUND & AIMS: The present study was undertaken to evaluate the role of serine proteases in regulating digestive enzyme secretion in pancreatic acinar cells. METHODS: Isolated acini were stimulated by various secretagogues in the presence or absence of cell-permeant serine protease inhibitors 4-(2-aminoethyl)-benzenesulfonyl fluoride and N(alpha)-p-tosyl-L-phenylalanine chloromethyl ketone. F-actin distribution was studied after staining with rhodamine phalloidin. RESULTS: Both cell-permeant serine protease inhibitors blocked amylase secretion in response to secretagogues that use calcium as a second messenger (e.g., cerulein, carbamylcholine, and bombesin) but not to those that use adenosine 3',5'-cyclic monophosphate (cAMP) as a second messenger (e.g., secretin and vasoactive intestinal polypeptide). Incubation of the acini with these inhibitors also resulted in a dramatic redistribution of the F-actin cytoskeleton. This redistribution was energy dependent. Similar redistribution of F-actin from the apical to the basolateral region was also observed when acini were incubated with a supramaximally stimulating concentration of cerulein, which is known to inhibit secretion. CONCLUSIONS: These results suggest that a serine protease activity is essential for maintaining the normal apical F-actin distribution; its inhibition redistributes F-actin from the apical to the basolateral region and blocks secretion induced by secretagogues that act via calcium. cAMP reverses the F-actin redistribution and hence cAMP-mediated secretion is not affected.
BACKGROUND & AIMS: The present study was undertaken to evaluate the role of serine proteases in regulating digestive enzyme secretion in pancreatic acinar cells. METHODS: Isolated acini were stimulated by various secretagogues in the presence or absence of cell-permeant serine protease inhibitors 4-(2-aminoethyl)-benzenesulfonyl fluoride and N(alpha)-p-tosyl-L-phenylalanine chloromethyl ketone. F-actin distribution was studied after staining with rhodamine phalloidin. RESULTS: Both cell-permeant serine protease inhibitors blocked amylase secretion in response to secretagogues that use calcium as a second messenger (e.g., cerulein, carbamylcholine, and bombesin) but not to those that use adenosine 3',5'-cyclic monophosphate (cAMP) as a second messenger (e.g., secretin and vasoactive intestinal polypeptide). Incubation of the acini with these inhibitors also resulted in a dramatic redistribution of the F-actin cytoskeleton. This redistribution was energy dependent. Similar redistribution of F-actin from the apical to the basolateral region was also observed when acini were incubated with a supramaximally stimulating concentration of cerulein, which is known to inhibit secretion. CONCLUSIONS: These results suggest that a serine protease activity is essential for maintaining the normal apical F-actin distribution; its inhibition redistributes F-actin from the apical to the basolateral region and blocks secretion induced by secretagogues that act via calcium. cAMP reverses the F-actin redistribution and hence cAMP-mediated secretion is not affected.
Authors: V P Singh; A K Saluja; L Bhagat; G J van Acker; A M Song; S P Soltoff; L C Cantley; M L Steer Journal: J Clin Invest Date: 2001-11 Impact factor: 14.808
Authors: Sarah Navina; Chathur Acharya; James P DeLany; Lidiya S Orlichenko; Catherine J Baty; Sruti S Shiva; Chandra Durgampudi; Jenny M Karlsson; Kenneth Lee; Kyongtae T Bae; Alessandro Furlan; Jaideep Behari; Shiguang Liu; Teresa McHale; Larry Nichols; Georgios Ioannis Papachristou; Dhiraj Yadav; Vijay P Singh Journal: Sci Transl Med Date: 2011-11-02 Impact factor: 17.956
Authors: Pawan Noel; Krutika Patel; Chandra Durgampudi; Ram N Trivedi; Cristiane de Oliveira; Michael D Crowell; Rahul Pannala; Kenneth Lee; Randall Brand; Jennifer Chennat; Adam Slivka; Georgios I Papachristou; Asif Khalid; David C Whitcomb; James P DeLany; Rachel A Cline; Chathur Acharya; Deepthi Jaligama; Faris M Murad; Dhiraj Yadav; Sarah Navina; Vijay P Singh Journal: Gut Date: 2014-12-10 Impact factor: 23.059