STIMULATED PANCREATIC EXOCRINE SECRETION DOES NOT REQUIRE PANCREATIC HYPEREMIA IN RATS - POTENTIAL CHOLINERGIC ROLE

Although blood flow and cholinergic tone influence gastric and salivar y gland secretion, their role in pancreatic secretion is poorly define d. The purpose of the present study was: (1) to test the hypothesis th at an increase in pancreatic blood flow accompanies stimulated pancrea tic exocrine secretion, and (2) to examine the effects of cholinergic agents on basal and stimulated blood flow using hydrogen gas clearance . Stimulated pancreatic exocrine secretion (secretin 0. 4, 0.8, 1.6 mu g/kg/hr) resulted in a significant (P < 0. 005) increase in secretory volume; however, pancreatic blood flow was not significantly changed, and a negative correlation between bloodflow and secretion was observe d. A pharmacologic dose of secretin (5.0 pg/kg/hr) resulted in a signi ficant (P < 0. 05) increase in pancreatic blood flow, which was inhibi ted by atropine (5.0 mug/kg/hr) infusion. Although 2-deoxyglucose caus ed a significant decrease (P < 0. 03) in basal pancreatic blood flow, atropine had no effect on basal blood flow levels These observations s uggest tha (1) under physiologic conditions, secretin- or 2-deoxygluco se-stimulated pancreatic secretion does not require pancreatic hyperem ia; (2) a pharmacologic dose of secretin does produce pancreatic hyper emia, perhaps through a local cholinergic mechanism, (3) peripheral ch olinergic tone does not contribute significantly to basal pancreatic b lood flow; and (4) basal pancreatic blood flow may be influenced by ce ntral mechanisms.