Duodenal acidification releases cholecystokinin

Area of Science:

• Gastroenterology
• Physiology
• Endocrinology

Background:

• The regulation of pancreatic secretion is crucial for digestion.
• Hormonal feedback mechanisms play a significant role in controlling digestive processes.

Purpose of the Study:

• To investigate the impact of duodenal hydrochloric acid (HCl) on cholecystokinin (CCK) and secretin release.
• To determine the effect of HCl-induced hormonal changes on exocrine pancreatic secretion in conscious dogs.

Main Methods:

• Conscious dogs with gastric and modified Herrera pancreatic cannulas were used.
• Intraduodenal administration of varying concentrations and rates of HCl was performed.
• Plasma concentrations of CCK, secretin, and gastrin were measured.
• Pancreatic secretion of bicarbonate and enzymes (trypsin) was quantified.

Main Results:

• Intraduodenal HCl significantly increased plasma CCK and secretin concentrations in a dose-dependent manner.
• Plasma gastrin levels decreased following HCl administration.
• Increased plasma CCK correlated with enhanced pancreatic trypsin output.
• Increased secretin levels paralleled augmented pancreatic bicarbonate output.

Conclusions:

• Duodenal HCl is a potent stimulus for the release of CCK and secretin in dogs.
• These hormones, CCK and secretin, play a key role in mediating the pancreatic secretion of both enzymes and bicarbonate in response to acidic stimuli.
• The findings elucidate a critical hormonal pathway regulating pancreatic exocrine function in response to luminal acid.