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Updated: Aug 14, 2026
06:04
Ex Vivo Intestinal Sacs to Assess Mucosal Permeability in Models of Gastrointestinal Disease
Published on: February 9, 2016
Gallbladder mucosal function: studies in absorption and secretion in humans and in dog gallbladder epithelium
1Department of Surgery, Fukuoka University, Japan.
The American Journal of Physiology
|July 1, 1992
Summary
Gallbladder bile changes from dark brown to opalescent white after meals, indicating active secretion, not just absorption. This finding challenges the traditional view of the gallbladder as solely an absorptive organ.
Area of Science:
- Gastroenterology
- Cell Biology
- Biliary Physiology
Background:
- The gallbladder is traditionally considered an organ for bile storage and concentration.
- Its role in active secretion has not been fully elucidated.
Purpose of the Study:
- To investigate the physiological function of gallbladder mucosa beyond absorption.
- To understand the dynamic changes in gallbladder bile composition postprandially.
Main Methods:
- Studied 35 patients post-percutaneous transhepatic gallbladder drainage for acute cholecystitis.
- Analyzed gallbladder bile composition before and after meals.
- Utilized cultured dog gallbladder epithelial cells to examine sodium flux in response to secretin.
Main Results:
- Gallbladder bile was dark brown and lipid-rich after fasting, becoming opalescent white and extracellular fluid-like after meals in all patients.
- Gallbladder epithelial cells demonstrated sodium absorption under basal conditions.
- Secretin induced a reversal of sodium flux, leading to net secretion in vitro.
Conclusions:
- Gallbladder mucosa actively secretes fluid, challenging its traditional role as only absorptive.
- Postprandial changes in bile composition are driven by neural, humoral factors, and active de novo secretion.
- Findings impact understanding of "white bile," gallbladder sludge, and enterohepatic recirculation.
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