Related Experiment Video
Updated: May 14, 2026
07:54
Cholesterol Efflux Assay
Published on: March 6, 2012
Diffusion of substances into human cholesterol gallstones
J R Sanabria1, G A Upadhya, R P Harvey
1Department of Surgery, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, University of Toronto, Canada.
Gastroenterology
|March 1, 1994
Summary
Cholesterol gallstones are permeable, allowing substances like fluorescein and proteins to enter and exit. Molecular weight influences the rate of diffusion into and out of these stones.
Area of Science:
- Gastroenterology
- Biochemistry
- Materials Science
Background:
- The permeability of formed gallstones to external substances has not been previously investigated.
- Understanding gallstone permeability is crucial for comprehending gallstone formation and growth dynamics.
Purpose of the Study:
- To ascertain the permeability of cholesterol gallstones.
- To evaluate the influence of molecular weight on the degree of gallstone permeability.
Main Methods:
- Human cholesterol gallstones were surgically collected and incubated with fluorescein, albumin, or immunoglobulin G (IgG).
- Substance egress was assessed by transferring incubated stones to buffer solutions.
- Stone and diffused dye areas were quantified; penetrating IgG mass was measured via ELISA.
Main Results:
- All tested substances, including fluorescein, albumin, and IgG, successfully permeated the gallstones.
- While all substances diffused out, proteins exhibited slower egress compared to fluorescein.
- Molecular weight demonstrably affects the diffusion rate into and out of gallstones.
Conclusions:
- Cholesterol gallstones exhibit permeability to substances of varying molecular weights.
- The findings necessitate consideration of diffusing substances' roles in gallstone pathogenesis and progression.
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