Related Experiment Video
Updated: Aug 10, 2026
09:34
Applications of Spatio-temporal Mapping and Particle Analysis Techniques to Quantify Intracellular Ca2+ Signaling In Situ
Published on: January 7, 2019
Changes in membrane cholesterol affect caveolin-1 localization and ICC-pacing in mouse jejunum
E E Daniel1, Gregory Bodie, Marco Mannarino
1Department of Pharmacology, University of Alberta, Rm. 9-10, Medical Sciences Bldg., Edmonton, Alberta T6G 2H7, Canada. edaniel@ualberta.ca
American Journal of Physiology. Gastrointestinal and Liver Physiology
|February 24, 2004
Summary
Disrupting caveolae in mouse intestines with cholesterol modifiers (CD/WSC) altered pacing by interstitial cells of Cajal (ICC-MP). These changes suggest caveolae signaling plays a role in gut pacing.
Area of Science:
- Gastroenterology
- Cell Biology
- Physiology
Background:
- Intestinal pacing relies on interstitial cells of Cajal in the myenteric plexus (ICC-MP).
- Caveolae, plasma membrane invaginations rich in caveolins, act as signaling hubs.
- Caveolins modulate signaling protein activity within caveolae.
Purpose of the Study:
- To investigate the role of caveolae and caveolins in ICC-MP pacing.
- To determine if caveolae disruption affects intestinal smooth muscle contractions.
- To assess the specificity of caveolae modulation on cholinergic responses.
Main Methods:
- Treatment of intestinal segments with methyl beta-clodextrin (CD) to deplete cholesterol and water-soluble cholesterol (WSC) to load cholesterol.
- Measurement of pacing frequencies and paced contractions.
- Assessment of responses to carbamoyl choline and cholinergic nerve stimulation.
- Immunochemical and ultrastructural analysis of caveolin 1 and caveolae.
Main Results:
- Both CD and WSC treatments reduced pacing frequencies, with effects reversed by the other agent.
- Paced contractions were inhibited, but reversal was incomplete.
- CD depleted caveolin 1 and caveolae; WSC altered caveolin 1 distribution but not caveolae number.
- Neither treatment affected responses to exogenous or nerve-stimulated acetylcholine.
Conclusions:
- Caveolae signaling in ICC-MP is implicated in intestinal pacing.
- Caveolae modulation does not influence cholinergic neurotransmission in the intestine.
Related Concept Videos
01:21G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
01:27Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...