PANCREATIC-JUICE DIVERSION AUGMENTS OLEIC ACID-STIMULATED PANCREATIC-SECRETION AND RELEASE OF SECRETIN AND CCK IN RATS

We investigated the role of intraduodenal (id) pancreatic juice, tryps in and lipase on pancreatic secretion and release of secretin and CCK stimulated by id infusion of emulsified oleic acid (pH6.5,10%,2ml/h) i n pancreatic juice-diverted rats. Id infusion of oleic acid caused sig nificant increases in pancreatic secretion and plasma levels of secret in and CCK. Id administration of pancreatic juice (200 mu l/h) or tryp sin(100mg/h) in combination with oleic acid resulted in significant su ppression of the oleic acid-induced increase in pancreatic secretion, including juice volume, bicarbonate and amylase output and plasma secr etin and CCK levels. However, oleic acid-increased pancreatic secretio n was unaffected by lipase (140mg/h). It is concluded that both secret in and CCK play a significant role in the negative feedback regulation of pancreatic secretion in the intestinal phase, and that pancreatic juice-induced suppression of pancreatic response to oleic acid is attr ibutable to trypsin, not lipase.